A833 question

440 6-packs & hemi's got the 18 spline input, which could also be had short shaft=rare.
The rest got 23 spline inputs and either long[b-e body] or short[a-f body] tail shafts.

All 4 spds came with the same [727 splined that is] short or long tail shafts.
3 spd's have 904 splined tail shafts.
You will find different shifter bosses-mounting flanges depending upon car.
E body had them up close to the case[foward]
B body had them most rearward on the end of the tail
A body had them just behind the trans cross member[middle]

I have seen a 66 904 splined 4spd though it could of been a hoax I did not pay it any mind, not interested in small spline ****, either way not desirable.

70' is when they started the dual B-E shifter bosses.

There are early and late side covers, the difference is early 61?- 70'has the trusty ball detent levering while the late uses spring loaded rooster comb crap levering.

And don't go for the 'ball and unbalanceable trunnion' 65' earlier i think.

You can put a B-E body length 4spd in an a body just as you can put a 727 in, but you have to make a shifter bracket out of plate and mount it to the b body [rear tail] pad and if it has the e body pad as well you need to grind the 2 bolt hole bosses down closest to the cross member.

I know cause that is what's in my car for 5ys now, you do what you gotta do with what you got sometimes.

good luck.