Some of the parts stores sell clutches with different sized input shaft splines. If they got you one with the wrong size, you will have all kinds of trouble. I know autozone lists two different "compatible" clutch part #s for mine but only one of them works.
Also, don't lever-type and diaphragm type clutches require slightly different clutch release throws and air gaps? Might want to check on that, I think Novak talks about it some in their knowledge base articles (novak-adapt.com). Might just be an issue of shortening your linkage rod so that the clutch lets out all the way if you're lucky.
Good luck and holler when you get things sorted out, I'll be interested to know what it turned out to be. I've had my share of clutch headaches.