I'm sure I didn't use shims, and there was no problem.
Mine is buttoned up, but fairly sure I simply reversed the rivet position you show in the first image. The shop head did not interfere with the flange, or if it did, a very very small flange trim took care of it.
RV-7A: Flying since April 15, 2012. 750hrs
YIO-360-M1B, mags, CS, GRT EX and WS H1s & A/P, Navworx
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