Lord B,
If you have not changed your nylon bushings you should and this could be the cause of your problem. I had the same problem after I had changed the nylon bushings. In addition to the shift tube there is a connecting rod. The connecting rod had come undone and was allowing the shift to flop about. I was able to re-connect the rod and tighten it up. It dramatically improved the feel of my shifter.
regards,
Ted 1969 280SL
PS: My shifter was in backwards for years. Does yours angle towards the front of the car?