I'd suggest looking at increasing the throw on the cable before pulling the engine.
Its a common problem even with the pinto, but especially (for some reason) with the redtop.
I had to try a number of quadrants and ended up with (I think) one from a Granada. Dont go by the colour, but by the diameter size, as aftermarket ones come in all colours. The quadrant itself is always the same size, but the groove comes in varying depths. You need one where the cable lies level with the top of it. MIne needs lifting a bit, ive fixed 2 cable ties, one on top of the other, into the groove before fitting the cable. Its all dismantled at the moment in the picture.
Do a search on this site, the resourceful guys on here have come up with a number of solutions.
If you do need a clutch, go direct to Helix for advice, they really know their stuff.