Pedal has to go to floor and still get some grinding

I tell you that I had a problem with my car that was driving me crazy a couple of years ago. One tell tale sign was that I couldn't get the car into reverse without shutting the car off and putting it into reverse than starting up the car again. Assuming that you have enough travel on the clutch to engage and disenage from the flywheel it might be that the pilot bushing is hanging up on the input shaft. My pilot bushing was slightly off and would catch on the input shaft. Once the pilot busing was machined properly the problem went away. I'm not saying that is your problem but food for thought.

Carl