you can always countersink the rivets. If the skin is too thin for standard rivets use the 1097 small headed rivets. I use these all over the place for platenuts, easier, and faster then dimpling platelets.
Tom Martin RV1 pilot 4.6hours!
CPL & IFR rated
EVO F1 Rocket 1000 hours,
2010 SARL Rocket 100 race, average
speed of 238.6 knots/274.6mph
RV4, RV7, RV10, two HRIIs and five F1 Rockets
RV14 Tail dragger
St.Thomas, Ontario Canada, CYQS