Not that this is going ot of much help but years ago I had a Turbo Action Cheetah shifter in my Dart with a 727. I took it out when I sold the car...and put it in my Ranger with a c-4. To get low gear I had to give up on park. Did not matter how I adjusted it, I could not have both. I took it to mean that the throws on the trans were a bit different so the gate that worked on a 727 would be different that the gate form a c-4. If this is true I would think trying to use a gm shifter would be a problem....I never verified this about the gate so....
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