1966 904 to a 1965 904 Transmission swap into a 65 Dart

I have a rebuilt mechanical linkage 1966 904 Transmission, and I am acquiring a cable shift 1965 904 Transmission core. I am building a 65 Dart GT Charger clone with a cable floor shift, and I would prefer to use the standard floor cable shifter that was stock in the 65. What would be a sensible recommendation for this swap.....rebuild the 65 cable shift 904 transmission and sell the 66 already rebuilt 904, swap the parts from the 66 904 into the 65 904 (if the swapping of the parts will work), or, not at the top of my preference, use the 66 rebuilt 904 in the 65 Dart with a different cable shifter (another member helped me with a plan to use a B&M shifter and some fabricated brackets). I would prefer to have the 65 cable shift transmission in the car as I am building the car partially for show so original/stock is a factor. Primarily, I just would like to know if these 66 904 parts will work in the 65 904 case? BTW, are 1965 mopar slant 6 904 parts the same as a 1965 mopar V8 904 since I also have a working /6 904. I know the bellhousing is different. I would sooner gut the /6 904 as opposed to using the parts from the rebuilt V8 904. I don't know a thing about transmissions, so, sorry if these are off the wall questions. Thank you, what would your advice be?