Today I had to redrill the rear spar doublers, 7 holes in each to fit the supplied M4 rivnut as the factory have recently moved from M3 to M4 rivnuts in most parts of the airframe because they are more robust. Drilled the holes out to 5.8mm then reamed them out to 6mm to give the rivnuts a nice snug fit (with high strength locktite). I removed the alodine with scotchbrite then realodined them ready for primer.
