C4 Transmission shift positions Question

Hey friends I have a question regarding the shift pattern on the C4 Transmission in my 68 cougar.

My current trans was given to me free by a friend who bought it new from I believe TCI and barely used it before converting his car to a 5spd manual. I had it installed right away and it works great though the shift pattern was different than what I was used to. I wasn’t a huge fan, but it was a free transmission with a peppy shift kit so I sucked it up. Plus my old one was non-original, leaked, and was shifting sloppy.

I’m embarrassed to say this swap was about 7 or 8 years ago and I’ve only just now learned by googling the right terms that the 65 Mustang he purchased it for employed a different shift position designations than later used in 68. I’d like to change this transmission to perform how a typical 68 would in each of the 1-2-D positions.

My question is: How difficult is it to convert a C4 to behave like a 68? I’m curious to know how involved this would be. Depending on what it takes I may tackle it myself, or enlist a couple mechanic-friends, or suck it up and deal until this transmission fails someday.

Please let me know if more details are needed, and thanks!

The early C4 like yours used a different pattern that was quickly revised to the standard version in 1967. You can change it by replacing the valve body and the shifter with the later version parts for a floor shifted transmission. It can be done with the transmission in the car. It won’t be easy or cheap. It’s the sort of job that can be done by anyone but might be best left to a pro.