Reply to "Big Block Ford Hydraulic Throwout Bearing"

Tilton says (and I believe them) that the single most critical dimension in an annular-piston throwout system is the 'free play' between the annular piston being bottomed in its bore. If the piston bottoms, it starts spinning with the clutch and those special seals are not designed for rotation, only straight-line motion. So within 50 miles, the seals wear out and total clutch function is lost. The systems are rebuildable but certain parts aren't easy to install correctly; Tilton will rebuild mine for $125. It also gets a bit tricky to set the clearance because when the engine, bellhousing/clutch and ZF heat up during a nice hard run, all the dimensions change noticably. Tilton recommends no less than 1/8" of free play at 'normal' operating temp, which with your system seems to make things worse. I definitely would check into getting a new nose/seal piece made with more threads! There's a LOT of force pushing on those threads during normal clutch operation.
All the Pantera vendors used to sell much the same system a couple of decades ago, but Pantera owners typically don't set them up properly and warranty returns caused all the vendors to stop selling annular throwout systems. The last one I remember being sold was by D. Quella in CO.

Not to discourage you; I like my system, its 8 lbs lighter than stock and far less mechanically complex, with almost no friction. A stock 11" clutch works very easy with a stock clutch master cylinder size. But it also requires the ZF to come out if anything at all needs attention.