Yep that clutch stop (made by pickyeater334) has been discussed a few times, definitely recommended mod.
Previous thread:
http://www.zpost.com/forums/showthread.php?t=503837
To adjust it you don't need to start the car. Simply put your key in the On position, then depress the clutch. You'll hear a CLICK when the relay engages, that's the highest clutch point that the car will start, adjust your clutch stop to be just past that point and you're golden.
Also as mentioned previously, make sure that after this mod you always depress the clutch all the way to the floor before shifting so you don't beat up your synchros.