The RPC should be here Tuesday. I also have a CXA QCTP and a set of 3/4" indexable tool bits coming. I have to machine the backing plate for the chuck. The chuck is a 12" 3 jaw Cushman, and the bolts go in from the front. They are in the center section, not the periphery like other chucks I have used. When I machine the registration boss in the backing plate, should I leave a gap like normal? The bolts will draw on the center section where there is gap, not sure if that will distort the backing plate and throw it out of square. Any ideas on this?