you will have to have a pushbutton small block trans, either the 727 or the 904. you'd also need longer cables as the slant 6 push button cables are about 4 inches too short. There is no converting a non pushbutton trans to a push button trans as the cases and internals are entirely different. Good news is, you can find small block push buttons all day long for less than 200 bucks. Cables will be an issue. Only one place is reproducing them and the reputation isn't great. Means you'll have to source small block cables, expect to pay 100-200 PER cable, there's 3 cables unique to pushbuttons. The parking cable, shifter cable and speedocable. Used cables are likely cracked and will need resealed to prevent leakage of ATF.
I kind of have a weird thing for push buttons ever since I brought my 64 polara home. so if you have any more questions, hit me up.
edit, one other thing, the cables are also unique between dodge and plymouth. length is the difference even on same body platforms.
