||Do you want to go stone-stock, or do you want to have some FUN??!! Want to get in the low range of that two speed axle a lot, or just put your foot down and keep on keepin' on?
My '65 Chevy school bus features a burly Cadillac V8 and, though it weighs 15,000 pounds loaded up, it'll just keep going on any grade up to about 7 percent. You pay a price in fuel mileage on the climbs, but you also don't have to crawl along in low either. The '68 and later buses are great for these conversions because they have a much bigger radiator area than my '65 does-this is the only problem I've had with this engine. It needs all the cooling it can get.
I can build you such an engine, and the cost is much more reasonable than you might think. Plus, when you open it up it sounds KILLER and scares all the ricer bois ;-)