Yes, not sure if the breakdown is 2wd vs 4wd, but I called on a '9X truck being parted out, 1/2 ton 2wd as I recall, and it had the 3500.
Two easy ways to ID it. First, AFAIK, all 3500's had fixed bellhousings. 4500's had the removable ones. Second, look the tranny code up in the glove box. The tranny code (RPO) should be MXX, M being transmission, XX being the model. I found that info online somewhere, much easier to call someone and have them look in the glovebox instead of crawling under the truck /forums/images/graemlins/smile.gif