The instructions that came with my Centerforce listed a spec of needing a mimimum of 1/16 th of an inch of clearance between the pressure plates fingers and the release (throwout)bearing's race (face) when the clutch is fully disengaged (petal all the way up). This makes sure you have a little slack (including slight metal expansion of your rod, bellcrank, etc. in your clutch disengagement assmebly to keep the bearing form spinning (engaging)with your foot off the petal.
The rato of the pivoted release (throw out) arm determines how much petal it takes to disengage the clutch.
I don't like a clutch too ride to high on the petal for comfort reasons and I feel a little bit better knowing the bearing is totaly off the clutch.
Loosenen the assembly even more will bring the engagment point of the clutch petal/arm lower as your foot swings it down. Just make sure the clutch fully disengages before the petal hits the stop or floor board.
We used to run the clearance pretty tight when drag racing to change("pop")gears quickly.
Too low (loose) of an engagement point will make your leg ache after a while.
Adjust the linkage (and reajust after innitial break in) to get to a comfortable spot in the arm's swing for you - making sure you have complete engage and disengagement.
Your adjustment rod allows you to get it "just right" and also allow for tweaking it later due to clutch wear.