6 in one hand 1/2 dozen in the other. 300 6 is a torquey little mill. Lot more durable than a small-block ford too. Its a great engine, IMO much better than a smallblock. They've got a really long life. When you want to move a truck you are talking torque, no question about it. The torque produced by a 302 and a 300 are damn near equal (actually the 300 probably produces more at a lower RPM). My point is, unless you're going to go big-block, a v-8 swap is not worth the time and money. Even a 351 isn't enough cubes to really wake up a truck. If you could find a stock or slightly modified big-block, that would really give you the power you'd be happy with.
I really built a small-block for an old ram (360 mopar with tons of goodies, check my pictures) and to be perfectly honest, if I had it to do over again, I'd go bigblock.
Just my .02 man, don't waste your time with a small-block-