Early 904 Transmission Upgrade
65 still had a cable-shift transmission (my 65 Dart & 65 Newport). The shift pattern might have changed (i.e. not P-R-N-D-2-1 which became a fed mandate ~1965). I heard various things on that. My 64 push-button shifter is currently out. I'll see how the buttons correspond to cable movement. I know the cable follows the above pattern in both my 65's.
Most rebuild kits state 1967+. I was able to buy the early kits. One difference is that 1966- trannys have a separate external park cable, whereas 67+ have an internal rod. I don't know that other internals vary much. I think my 65 drum bands are more like the "hemi bands". They are split, so make several effective wraps of the drum. That is why you adjust the play more (5.5 turns I recall). I heard one can use a later band. I would expect that clutch plates are the same, so you could use Blue Plate Special or such. I put a shift kit in my 65 727 and don't recall it being a special PN. You can buy almost all internal parts separately, so checkout the PN listings on those websites. Don't just go by the rebuild kits, since they might just differ in a few seals. Insure you use the early filter (2 holes?), since putting a later filter can starve the (rear?) pump and ruin it (I read).