I think you can check the detent spacing. Here is an idea. Install the shift cable completely on the transmission end. Install only the clip that holds the cable in place at the shifter. Don't install the cable end (eyelet?) to the shifter. Put the transmission in a gear detent position. Put the shifter in that same position. Does the eyelet of the shift cable line up with the post it would mount on? This check can be done in several or all gear positions.
Feel free to respond if this is not clear.
Have a great weekend,
Paul Lohr