Using Monel flat head rivets that are proper diameter for 10-32 nutplates, thus no need for dulling drill bits when drilling out nutplates to 1/8". Since head is kinda small, it's hard to get an exact depth with 120 degree 3 flute countersink, and even if you do it reasonably, shape doesn't exact/exact match the shape of rivet head. Probably fine if you just rivet (perhaps slight motion), but if you put a dab of JB KWIK under head, all is very nice. Flange is only 3 BID which doesn't help.
Y10-04-23