Adjusting clutch via cable?! Is this my prob?

I have a zoom clutch, adjustible clutch cable, quadrant, and a firewall adjuster. Last year when I installed that cable I didnt but the stop nut on the end of the cable because I didnt know what it was for until I read the instructions after the installation .

So my 1st question is could that nut unscrew its self over time?

And If I tightend that screw would that make it where as the clutch engages the flywheel at a lower pedal level? (Does that make sense)

Im asking this because my clutch doesnt engage till my foot is ALMOST off of the clutch pedal and it also seems like the clutch isnt grabbing the flywheel hard like it used too. And I drove my friends stang the other day and his clutch engages as soon as you take a little pressure off of the pedal.

Well Ive been told that its normal and the clutch is suppose to engage/disengage from the flywheel at the top of the pedal. SO I got under the car today and unscrewed the adjuster nut and the clutch grabs better but if I can unscrew it about an half inch more it would grab just perfect. But the problem is that the nut is already at the end of the threads on the cable and the firewall adjuster is screwed all the way into the firewall. So what should I do?

ttt

No slack in the cable... and the more I screw that nut on it seems like the clutch isnt grabbing. And the more the screw is backed off of the cable the better the clutch grabs.