Well that is a whole different issue than I faced. I wanted to get rid of the 1 year only 65, cable shifted (front u-joint name is escaping me, Detroit joint?) obsolete front u-joint tranny. I built this car like it was going to be for me, upgraded the weaknesses (7 1/4 gone in favor of 8 3/4, dual master cyl etc. ) but I wanted to retain the stock appearance as much as possible.
So I found that Imperial Services makes just the cable to go from the stock shifter ($175) to the later model 904. You need to make the call, are you wanting to keep your pushbuttons? They just may make what you need if you are wanting to go to a later trans.
Is your emergency brake on the end of the trans? I can't remember which year they stopped doing that.