So, after many aborted printing attempts, I'm getting closer to something useful. First were issues with the resin. I'm using Elegoo ABS-Like, as I wanted something that can handle some handling without breaking from being brittle. Works fine on the smaller printer (that's what I printed the truck sides in), but when dealing with large prints, I was getting a lot of support failures. Tweaked (and tweaked, and tweaked) the settings, and finally got close to something usable.
The walk on the roof warped all to **** after the supports were removed. Same thing happened along the sides with the bracing. Sadly, anything close to scale thickness just isn't as structurally supportive when printed in resin instead of fashioned from steel. I may be able to get around this by printing the body in smaller pieces, curing them with the supports attached, then assembling it afterwards. I've already modified the model to allow this to happen.
I do have some useful parts. The helium tubes are good, as are the ends (with the exception of the ladders and some of the grab irons).
Detail on the door ends came out good, ladder will be removed, printed separately, and attached.
Same thing with the ladders on the brake end. Brake wheel came out good, connections from it will be made with chain and brass rod.
Still more work to do, but progress made!
