Pushbutton to 4 speed 64 Dart

Only issues I know of "from reading" are you don't have much bell clearance (seam in the tunnel?) and you likely have the flanged drive U joint you will surely want to go to a later transmission with slip joint, so new driveshaft made. And of course you'll need an "A body" 4 speed (short shaft and shifter location) and of course A body linkage and tunnel "hump."