Try HR Clutch in Bensalem, PA. Yes, I know, shipping. But this is a second generation clutch shop and they have been rebuilding my clutches and pressure plates for a good many years (30 plus). The last one the did for me was an old Schieffer high performance diaphragm pressure plate that I ran for years. Turns out they likely built it originally as they were the source for all of the Schieffer products when George Hurst purchase Schieffer and moved them to Glenside pa. Little more expensive but worth it I think to not have to go through the aggravation you are going through at the moment.
http://hrclutch.com/
