Its a old post but I thought I would add what I am working on. I have a 68 short bed 4x4 gmc that I am doing a mild restoration on. It currently has a 350 in it with a th400 trans and 205 transfer case. But I have a 250 from another 68 truck that is going to be swapped in. So far I have added 3/4 ton running gear and all new power steering, a 2 inch lift and 33 inch tires. The gas tank is from a 72 Blazer and is relocated under the bed. I decided to go the 250-6 route because it seems I have already been there done that with the V8's. I just bought a small 23 foot camp trailer today so now I am wondering if the 250 will have enough guts to handle the 3000 or so pounds. Hmmm
