Clutch release failure - opinions please...

Hello,

Tried posting this earlier - no joy. Anyway, i have an early '99 Jetta
WE; 2.0L, 020 transaxle, pretty heavily modified.
It's blown (Neuspeed supercharger) and that might provide some insight
here.

The problem is the clutch doesn't fully disengage, even if the clutch
cable is adjusted too tight.
I've pulled the endcap off and checked the operating lever, TO
bearing, and release rod. All look good.

If the clutch cover disintegrated wouldn't the clutch fail to engage?
Or if the release fingers are bent, shouldn't there be a real racket
as the assembly rotates? at the least, wouldn't there be a horrendous
vibration transmitted through the clutch cable to the pedal? If the
thrust plate retaining spring failed - could it account for the loss
of motion?
(obviously everything I can check without splitting the gearbox from
the engine has checked out OK)

All input is appreciated - I'd like to have the parts on hand before I
undertake this repair.

Thanks!