UPR adjustable Clutch quad, and Firewall Adjuster Question

Basically, you pull the rubber grommet off the clutch cable, as the firewall adjuster (FWA) takes its place against the firewall. In order for the cable to plug into the FWA after you pull the grommet off, you'll need to file or clip or otherwise trim off those four little tabs that held the grommet on the cable sheath. Once you've got those off, the cable should just poke right into the FWA. It'll be a kinda loose fit, but rotational tension is irrelevant, as your main concern will be with the actual cable tension more than anything else.

Assuming you're using the stock cable, you'll likely wind up using the first hook on the triple-hook quadrant, closest to the firewall. Go underneath and put the other end into position on your clutch fork. Then crank the FWA out (counter-clockwise, I think) to take up the slack in the cable. Easy way to gauge this is to pull foward on the cable sheath until the quad catches it, then hold that with one hand while screwing the FWA out until it presses up against the back of the cable sheath.

From there, you can start the car (in neutral, of course) and fine-tune the pedal height to your own liking. Put it in gear and let the clutch out SLOWLY until you feel it starting to catch. If it's hard to put in gear, you've got the cable too loose (too much slack) and need to screw the FWA out farther; if the clutch catches with the pedal too high, you've got it too tight (screwed out too far) and need to back it down some. I've found it works best to go with one- or half-turn increments at that point. Once you get it where you like it, lock it down with the locknut and you're set.