Can't see. Hit what you think is the bushing lightly with a file on the outside lip, away from where the input shaft inserts. The file should skate lightly on the steel of the crank and dig in easily on the bushing. Try both, avoiding seal or mating surfaces.

A good way to check would be to go to the parts store and check the books -- there is a crossreference by dimension, and you should be able to look up the application and back out the actual dimensions to verify against what you measure.

If you are confident that it is a bushing, you should be able to tap threads easily into the bushing and yank it. Odd that the bushing is driven so far in that it bottoms... makes it tough to use a proper puller.

I follow your measurements -- just be sure to remember that the Novak site has general rules of thumb, and they don't always work so well on non-Jeeps. I made sure I'd have extra throw for adjustment, and based my calculations on ACTUAL measurements. About 3/4" at your throwout bearing seems about right, IIRC the Isuzu slave swung about 1.25", which should allow a good cushion for adjustment, and with the pedal swing, a good range of actual foot travel.

Can you build a bracket that reaches inside the bell to hold the clutch slave, but fastens to the outside of the bell? Either that or use an extension rod between the clutch slave and the clutch fork? Does the clutch fork swing across the plane perpendicular with the tranny mainshaft centerline (effective leverage)?

Randii