Working from memory... The hex shaped on the backside of the Fork (toward the back of the car)should be the only thing you need to turn to adjust the Clutch.

That hex shaped is all one piece with the whole plastic part that fits through the Bellhousing Mount. That whole plastic part is threaded onto the Coil of metal sheathing that covers the cable.
As you turn the Hex shape, the whole plastic piece should move inside the Bellhousing Mount.

For proper adjustment, you should be able to slide under the car and push the Clutch Fork toward the back of the car about 1/8". That assures that teh clutch is totally disengaging and it is the proper slack so when you do press the clutch, it works the Pressure plate properly.
See if it is adjusted that way.. With the pressure needed to engage the clutch.. I think the Rubber boot is not interfering.
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