!! okay....for me the rusty holes in the cab and doors was the least of my concerns , i will cutout the bad pieces, weld new in place, no problem, it will take some time but there's no rush, and like with my other projects there will be something that pops up when under constructionAll of those mechanical deficiencies will take a half day to fix. Dead batteries are to be expected.
The only reason I would hesitate is if the rust you describe is actual holes in the metal.