early 904 question

the 904 i have is from a 65 Barracuda.
it has the ball and trunion output.

The 65 904 is basically a one year only transmission. It's dual cable operated - one cable for the park and the other for everything else. You would need to use either a 65-only dual cable column shifter or a 65-only cable floor shift.

should i use this trans or find a later slip yoke trans?
its going behind a 65 or 66 273.

If it were me, I would go with a 66 or later 904. 66-67 and maybe real early 68's used convertors with the small snout witch would fit your crank.

are convertors ( stall ) availible for that early trans?

Yes but most likely will be a custom order.

what about valve bodies for the cable shifter?

They are different than later ones.

If you go with the later 904 and use 66/67 buckets, you can use the 66-up console and floor shifter. If going with a column shift, you'll need to use the 1 year only 66 column shift. Might be able to adapter the 67 and later column, but haven't tried that.