While waiting for the 120 degree countersink bit to show up, I skipped ahead in the instructions a bit. I countersunk (100 degree) the 3 #40 holes on each side of the spar stub assembly. Then I deburred and prepped up the flaperon hinges (I think that's what they were, anyway). Four of them.

I'm not priming a lot on this plan but wing spars and ribs and anyting exposed to the elements I am. So I ran over to NAPA for some 7220 rattle an primer and primed the parts.

I'll finish riveting them together tomorrow. The AN AD4-4 rivets called out here are slightly short for this but I pressed on anyway.