WME

Wow are you going to have fun. A pure WAG is the white wire in the second photo of the first is the control wire for the isolator. Isolator is black cylinder in the first photo of your last post. With the engine off you should have 0v on the white wire, with the engine running there should be 12-14v on the white wire. If this is correct then check the isolator terminals one side should be 12v and the otherside 0v with the house battery disconnected. If both are so, then hook the white wire to the B terminal on the isolater. Start the engine and check the isolator for 12v on both sides. If thats good then hook up the battery + and check the house batter for voltage with the engine off. That should be less than 12v. Start the engine and the battery voltage should be 13.5v +. If that happen you good to go and as you drive around the engine will be charging the house battery. I can't tell is your isolator is a 3 post with a blob of rust or a 4 post with a broken terminal. Finding the battery V drain with the engine off and the ignition key removed requires a mini amp meter and you have to check each wire to the + post on the battery. Have fun

Get a cheap voltmeter and remove the wires from the battery. Check each wire with the ohm function to a known ground. Who knows what has been done in the last 35 years. You may have multiple grounds. With the wires disconnected, start the engine and check for 12v on the wires. Wire the battery according to what you find. After you get the battery hooked up to the basic wires connected, follow the other wires to see where they go. This is what your looking for, an auto reset circuit breaker...https://www.delcity.net/store/12V-Auto-Reset-Circuit-Breakers/p_198669.h_198846 Available at any auto part store.

"normal" RV wiring is black is +, white - YMMV depending on what silliness the previous owner has done.

It takes a few parts to do it right. These will save you a bunch of time and money in the future. https://www.homedepot.com/p/Camco-Pump-Converter-Winterizing-Kit-36543/205808441 You cant just pour antifreeze in the city water hook up. This will let the water pump suck the antifreeze direct from the jug. This is for the water heater. It will save you about $20 each year if you don't pump 6 gallons of antifreeze in the heater, it will also make the water taste better next year. https://www.homedepot.com/p/Camco-Quick-Turn-RV-Permanent-By-Pass-Kit-35983/205808443

Full discription...1991 Toyota Pickup C&C DRW 3vze 3L V-6. C&C means cab and chassis. DRW, dual rear wheels. Winnebago just added the house. Everything should be a standard pickup, until you start to do things to the rear axle, then the C&C, DRW and 1 ton Full Floating rear axle are needed descriptors . P.S. Winnebago, Itasca same people

With it running on electricity, open the back cover and feel the heater tube. It should be warmish hot. Its a tall vertical tube. Switch to LPG there should a small flame at the bottom. The tube should still be hottish after several hours.

Random things... Did you crack the tank on the bump? Get a garden hose and slowly fill the tank through the toilet. When its full to the top of the flange. Look around outside for leaks on the ground. The toilet/flange seal is foam. Its cheap and an easy replace. https://www.pplmotorhomes.com/parts/electrical-plumbing-lp-gas/rv-toilet-tanks-plumbing-sanitation/toilet-floor-gasket-kit_83-8794 Driving with a window open will create a low pressure zone in the house and suck the smells from the toilet inside. Helpful things to create low pressure in the tank. Ive used both and they work very well. https://www.etrailer.com/RV-Vents-and-Fans/Camco/CAM40595.html https://www.etrailer.com/RV-Vents-and-Fans/Lippert-Components/LC389381.html

Look carefully at the clear cover. Two sides will have tabs and the other two won't. Squeeze the two sides with the tabs. They should pop out of the slots in the yellow body. AND you have removed the light bulb cover.

Have you been here? https://www.boundfornowhere.com/blog2/build-out-week-1-2

Depends on temp and duration. If the low temp is above freezing, make sure you have propane and the heater works. Then just go for it. 0 to freezing winterize the rig and use bottled water, mix up a 1/3 antifreeze 2/3 water and use it to flush the toilet. Below 0 be in a camp ground with shore power and use a small electric heater to save propane. 50/50 antifreeze for flushing. Below -20 stay home😂

Maybe, for sure give them a call. https://www.pplmotorhomes.com/parts/rv-appliances/air-conditioner/air-conditioner-parts-accessories/replacement-shrouds/dometicbriskair-shroud_08.0004

Make old plastic new...😎...https://www.youtube.com/watch?v=Cz-HSjGj0ek

Depending on the size of the hole, this may make things a lot neater. https://www.jamestowndistributors.com/userportal/product.do?part=32888&engine=adwords&gclid=EAIaIQobChMIhK_9gYve5AIVhBx9Ch0qQAdPEAQYBCABEgLv5_D_BwE

The local cheap gas station is about 4 blocks from my house, so thats what I use. About 2x a year the car gets a bottle of Techron. At the beginning of the RV season the MH gets 2x bottles, big fuel tank. After many years still good.

I get the not secure warning. W10 and Firefox. I also run Ghostery and an ad blocker My anti virus is Webroot

https://www.yotatech.com/forums/f197/new-project-ultimate-toyota-rv-rehab-299416/index2.html

The fuzzy thing is called a windlace. https://www.albrightssupply.com/windlace-s/2014.htm

Maybe something...... The blog "Bound for nowhere" shows the owners doing the stripes on a Sunrader. They uses a local company Carbon Wraps in Orlando FL. CW may still have the computer files. Carbon Wraps. 321 804 2726

OK here is a new idea. ATS $60 Easy Start $300...https://www.microair.net/collections/easystart-soft-starters/products/easystart-364-3-ton-single-phase-soft-starter-for-air-conditioners?gclid=EAIaIQobChMIw5rA1eDL5AIVAR-tBh348QENEAQYASABEgJqFfD_BwE&variant=30176048267 The outboard ATS will take the power from your exhisting inverter and direct it to the 115v ac house power panel. The easy start will reduce the start up surge from your Roof AC from 42 amps to something around 16 amps. Your 2000w inverter should be able to handle that. I don't know how happy the AC will be running on a modified sine wave. Ya pays ur money, an makes ur choices.

The vent line has to go uphill with no sags.

My floor lay out was different, but effectively I used the equivalent of a banister pole at the sink and one at step well dinette corner.

Good news, bad news. You can do it, but your are going to spend $$ to do it. Assumptions you have 4 t-105 or GC-2 batteries. Thats 450AH. Safety discharge means 225AH of usable power so your house mechanic is consertive on his time numbers. You have a typical 13.5k BTU roof AC. SO your looking at 1400w running and 5000w to start. So you going to need a bigger inverter. Also some serious battery cables. Your start up current will be drawing 450 amps from the batteries Stuff you need A 30 amp ATS will run $60. Plan B something like a Xantrex Freedom X-3000 inverter. It is a pure sine and can deliver 6000w for 2 sec, it also has a built in transfer switch. $850.00 Options A new generation smaller AC will draw less power and increase run time and reduce start up power needs. But thats even more $$. Like 1100w running $600 UBI the 11K Colman will run off a Honda 2200w generator. $1000.00, but then you have power when you need. Like a microwave.

Those windows appear to be Hehr. There 2 seals on those window. The brown rubber thing is NOT a seal. The window is sealed to the frame with a automotive urethane adhesive. The frame is sealed to the RV using butyl tape. So the drill is to remove the brown rubber strip, AKA glass glazing bead. You need 2 people or lots of duct tape for the next move. Using a razor blade or fillet knife, from the inside cut between the window and frame. Carefully start in a corner and push the window glass out of the frame. Then use a screw driver to remove the screws from the inside of the frame and separate the two parts. The outer frame is stuck on with butyl tape. Remove everything and clean things up. Mark the inner and outer frams so they will go back in correctly and the screws holes line up. Install new butyl tape on the frame and install the outer half. Screw the inner to the outer. Let the tape warm up and tighten the screws. If the tape oozes out just trim it to the frame. Make a bead of the urethane around the inner lip of the frame and set the window in it. Use some tape to keep it from shifting. Now install the glazing bead and cut it to length, Glazing bead match your profile...https://www.pellandent.com/RV-Window-Seal Window urethane...https://www.amazon.com/3M-08693-Urethane-Windshield-Cartridge/dp/B000RW1XCK Butyl tape, look around it comes in 3 colors...https://www.amazon.com/Dicor-BT-1834-1-Butyl-Seal-Tape/dp/B001FCB4JS Optional, this will keep the putty tape from accumulating guk, a small bead around the edge. NOTE this not self leveling lap sealant...https://www.amazon.com/Dicor-551LSW1-White-Non-Sag-Sealant/dp/B003YJLIW8/ref=pd_cp_263_3?pd_rd_w=mX8dV&pf_rd_p=ef4dc990-a9ca-4945-ae0b-f8d549198ed6&pf_rd_r=ETXT565S1WDVFWZSD34E&pd_rd_r=27d7fe2b-f8e4-4f84-8ec3-ce5be6c82132&pd_rd_wg=lOwge&pd_rd_i=B003YJLIW8&psc=1&refRID=ETXT565S1WDVFWZSD34E

Before a valid answer, we need to know what brand and model of inverter. Does it have a built in transfer switch?

In the photos your roof is black. If it is black then it has been coated with something NOT designed for RV use and you can see cracks in the covering. Those are leaks waiting to happen. Probably something like this stuff...https://www.lowes.com/pd/BLACK-JACK-4-75-Gallon-Fibered-Waterproofer-Roof-Sealant/3009900 To to make your roof right you can look forward to hand scraping the entire roof down to the metal, can you say days of scraping. 😫 Some auto cleaner chemicals may help, Like WalMart carb cleaner. If you use chemical help make SURE you outside, well vented and away from flames. When you get it cleaned off use lap sealant on all the roof seams, then use something like this on the roof...https://www.menards.com/main/building-materials/roofing-soffits-gutters/roof-coating/sealbest-duck-coat-white-thermoplastic-roof-coating-9-gal/1531835/p-1444444997118-c-5822.htm?tid=-4411091524350413458&ipos=14 It will stretch and not crack. It will also be a lot cooler and a bit quieter. Good luck