Well my 68 mustang came (to me) with a 302 and a FMX tranny. I've since then built up a new 351W and am ready to purchase my tranny. So what do you choose? At this point I'd like simpler. So I'm pretty sure I'm dumping the auto - T5 Conversion idea due to the amount of parts I'd need to acquire. C4 sounds the easiest and has the most parts available to hop it up, and I don't really drive on the highway at all. What about driveshaft? Would that have be changed?