Gas pedal conversion for dummies.

I have the rod linkage in 2 different slant six cars, Dart GT/904, and a Valiant with the manual 903. I don't mind either? The Valiant is like a cloud, just a tiny blip presses that pedal to the floor.
I have the cable on my Charger 318/904 and it feels like I'm pushing through cement sometimes.

I guess I'm asking why do you want to change it?