Wow did this turn out to be problematic. So the solution to my heavy handidness with the grinder was indeed bushings, but not on the bolts but in the main gear itself. My good frien Al, who literally has a machine shop in his hangar suggested enlarging the four notches and installing bushings with epoxy and dowl pins. The front two went perfectly, then we took the gear to the plane for a test fit. It turns out that the bolts in the weldment are not exactly square, so the center to center measurement where the gear will actually sit after adding the rubber shock absorbers was different from where I had measured!!!....which was at the bottom of the bolts, so beware and measure where the gear will actually sit. So for the two rear bushings we waited to epoxy and pin until getting it in place, so the bushings could rotate to the perfect spot...then we marked them. A lot of time and effort but it came out really good and fits perfectly square to the airplane with no extra movement, fore/aft or lateral.
