Different clutches/pressure plates have different thicknesses. Scrap the adjustable cable and purchase a MM new cable/quadrant/firewall adjuster set. You will thank me later for the smoothness of the pedal and ease of adjust-ability.
I purchased the MM kit today. But I want to shim this thing somehow until it arrives next Thursday. I'm thinking maybe at the firewall with washers? Or maybe I can put a little aluminum bushing between the fork and adjusting screw? It only needs to last a week. Thoughts?
EDIT:
Plan A: Find another nut with the same threads as the cable adjuster. Remove the jam nut, dome nut and drill a hole in the dome nut so that it slides over the cable adjuster threaded part easily. Put a stack of washers between the modified dome nut and the two jam nuts and reassemble on the threaded part of the cable adjuster. Tighten up the jam nuts until there is no slack in the cable.
Plan B: - better of the two solutions:
Remove the bellhousing and increase the height of the throwout bearing pivot stud. This will cause the cable end of the throwout bearing arm to move towards the rear of the car. You will probably end up redoing this once you have your new cable /quadrant/firewall adjuster setup.