With the gasket held by the rear screw and the original nut plat…

With the gasket held by the rear screw and the original nut plate, set a hole saw over the support arm hole so it totally covers it, but doesn't hang over the gasket, then mark & punch the center. I think this is a 1 1/2" hole saw, but I'm not sure.

Owner caption July 2003 · Photo 84 of 6546