I've looked around a bit concerning your tuner issue and this is what I've found.
I don't think Kluson style tuners will match the screw holes used for the open backs but if the shafts are right, the Klusons will probably cover the old holes. Here is a diagram showing the dimensions of Kluson style tuners for you to check against your Heit:

If they look like they will work you can order them here:
I think you should also consider repairing your open back tuners so they work better. I've found that with a little coaxing, I can get the old open backs to hold tune pretty well. I wouldn't trust them at a gig but for recording they are adequate.
The open backs can be completely disassembled and worn parts replaced. If you want to go this route, let me know. I have a good selection of open back strip tuner parts around here. sbStatistics: Posted by VintAxe — Sat Jun 16, 2007 12:51 pm
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