Had a few minutes to spare, so I deburred both sides of the rib flanges for the right wing upper surface of the leading edge skin. Then started to dimple about 3 ribs. With the deburr first, the rivets fit in the holes very nicely now.
Also received the Heyco 2820 bushings today, so I popped them into the rib holes to support the pitot / static lines that will have to be run before the skin goes on.