Had a discussion about this with the guy from Comp-u-flow at Carlisle. He says one of the biggest mistakes is overtorquing those bolts. 30 lbs is all they need regardless of the setup. No matter what you're using its still going into the same ALUMINUM hole !!! Also, your turned down bolts were likely for really thick-walled shafts. Harland Sharps don't need turned down bolts or studs. Studs go in finger tight, the nuts get torqued.