'65 Barracuda 318 LA Transmission Questions

You will likely need a new driveshaft too since 1965 was the last year for the ball & trunion "Detroit" fwd U-joint. Engines 1968+ (or so) have a larger crankshaft hole for the transmission torque converter snout, so need a spacer. Not an issue if the trans is similar year as engine. I haven't fooled w/ manual trannys, but recall reading that the crankshaft has to be deep enough for the pilot bearing, which might not have been true if the engine was came w/ an automatic. Don't quote me, but research.