Try the adjustment at the pedal. You may have too much play. I am talking about the adjustment on the pushrod that links the pedal to the master cyl. If that's not it, you may need a new clutch or hydraulics. Good luck!!!
Have someone push in the clutch while you observe the slave cylinder rod movement. It is also possible that the clutch fork that the slave cylinder pushes on is knocked off of the pivot. Was the car sitting for a long period? I have seen the clutch, pressure plate, and flywheel rusted together. Good luck! Joe
Since a 2+2 clutch uses a 9 bolt flywheel, I am curious how it would have worked on the coupe flywheel.
You can use a 2+2 clutch/flywheel setup, but you must also use the throwout collar for the 2+2.
Anyway, I'm glad you figured it out. Joe