Questions from a newbie...

Argh, AJ!!! You give me too many ideas, I literally can't decide.

So, this morning I see a '72 Duster with 3 speed manual near me. The guy has a 4 speed to go in the deal too. I'm assuming the pedal set up and other components would work with the 4 speed, correct? Obviously, new rods/linkage would be required. Do you know of any problems going from the 3 speed to 4 speed?