I've seen a 40 ford P/u on a S10 chassis, looked like a good fit. I just put a 51 Merc on a 83 Olds frame for a friends stepson, and that turned out to be fairly easy. I've also heard of using a ford ranger chassis, but I don't like the front suspension. The van frame might be a good fit, but check out the steering box mounting, might cause problems. Hank