Gutting a very trashed trailer - what to take/keep?

You're on the right track. Take everything that is usable and salvagable, even if you don't have a need for it. You may be surprised at what people need that you may think is junk.
Lighting, hardware, trim, appliances, etc. Then you can recycle the siding.

The stove is a 3 burner Wedgewood(?) stove. Ill clean it out and grab it today if I can figure out how to get it out. The table is MDF I think and very wet. I was going to check it for hardware later. How about the sink? It is a double stainless steel. I appreciate your help!

Lighting fixtures, in some cases, can be worth having. Even ones that have been wet can be dried out, and sometimes the finish will hold up too. 12-V lights might hold the "guts" you need for the gas lamp conversion. Older original glass globes are worth a few looks too.

I'm in with Vikx... hardware. It holds up the best under the worst conditions, and remains a useful placeholder in any vintage-nut's toolbox. Door handles and drawer handles can run into money when a lot needs to get replaced, and extras are good.
I would not worry about gimp. But table and counter edging, if accessible is worth a look. The table mounting hardware is still a find, even if you don't take the table.  Get the mounting from the wall as well.
I find appliances and windows both to be iffy, because in the case of windows, lots of trailers have some which are unique sizes. Folks replace appliances because they are not sure if they work and they are old, and worst of all, they cost a small fortune to try to transport if someone were looking for one shipped. However, the various parts, again (burner knobs, burner rings, grates, racks) are again handy to have in your stockpiles, there is always someone looking.
Small things like towel racks and such too....Oh...don't forget to look for the Sun Lite 400...with the globe. Shasta wings are a good find too....I have yet to beat the crowds to find any. (But only if the trailer is a Shasta...)

Free windows and the education that comes with them is hard to complain about, especially if you have the storage space to keep them. I have a couple trailers' worth myself. The best way to remove the door is right by its frame. Remove the screws and pry the putty loose, just like the windows, and take the entire unit as a whole.

Folding bed hardware? Piano hinges? Nice score....

Toilet training is always fun. I don't know for sure if it is one that will be worth saving...there were a few that definitely were not... The hold-down on the Aqua Magic models were a bit tricky, as the bolts are enclosed in the housing. Others were not so hidden. Just remember your cutters to sever the supply line.

Other exterior stuff is obvious, markers and tail lights, license light, porch light.....step....vent covers... We've covered the propane stuff before, I would not bother with anything to do with the propane unless the rack itself is in excellent condition. Regulators and lines stay behind.

The step may be near impossible if it is welded on, as well as the bumper. I would not worry about the bumper, as it probably will be welded as an integral part of the frame. Since you are having new frame done, just have it built in to it. Simple clean and neat.

I am not familiar specifically with the Wedgewood stoves, but it probably will be screwed into the cupboard surrounding it on its sides, and through the base into the shelf it sits on also. (Just as refrigerators are mounted to the floor and sides, from an earlier line of question.)

Gotta admit to being jealous of this mission, seems a lot more fun than the mission I have been on...

Here is a construction note for you...the gold colored trim in the bathroom was used with putty tape behind it to seal the corners of the walls in the wet bath (shower).

Putty tape/ putty is the devil. My arms hurt from prying the windows away from their putty. Yuck. The bathroom in this trailer is just a toilet and some shelves like a closet. It doesn't look like there was a shower in there. But near the door of the trailer there is the remains of some weird curtain thing that I keep thinking might have been a shower. It's not. In the bathroom tho. Ideas?

I did just find your photos on the other post. It definitely has some nasty qualities about it. Don't get in this so far you end up sick. The education is great but not worth that.   But you've got a lotta balls going in there, for sure...



Now that I rethink the toilet connection there is a good chance it is copper water line, and should cut loose the same way the stove did.  A small copper-tubing cutter is ideal for tight spaces.  I also carry a pair of Channellock brand wire cutters.  They aren't cheap (I think about $22 in the hardware store)  and they work.  Remember the bigger the handles that will comfortable in your hand, the better the leverage, the easier the cut.  You don't have to spend that much, but I like mine.  New ones of any "real" name brand are worth the investment for all your wire-cutting work, and will cut though soft plastic water line and most staples and thin nails as well.