First things First Dave, you need to decide what the purpose of the truck is for. I agree with many of these opinions here, and to break then dowm and find the one that works best for you, in your wants, needs, budget and being practical, you need to decide the main purpose of this vehicle. Is it your daily driver and going to be driven out of town, or just across town? Or just to go pick up a piece of furniture the wife bought at the local store as an occasioanl use vehicle. If its occasional use, I like the used motor idea for sure less money tied up. If you work quite a distance from home and driving it daily, then rebuild the 350 OR do the crate motor thing. Beleive it or not, many times you can get a good crate motor with a warranty if you know its from a good builder, and you can get one for cheaper than you can build one, and if you build it yourself, you do not have a warranty. Thats just my .02, actually as long as that was, I think it was a whole nickel.