Today I finished riveting the right flap. Then I frabricated and install the brass bushings on the flap brackets. After inspecting the right flap I noticed a few of the rivet hole on the outboard ribs looked cracked. After further inspection I confirmed that the inboard rib did indeed have cracks in it. I think its because of how thing the ribs were and the rivets weren’t lined up straight when I squeezed them. So I drilled out all of the rivets from the outboard rib and removed it. I inspected the left flap and noticed two holes with cracks on one of the nose ribs. Luckily I was able to enlarge the holes and use a larger rivet to remove the cracks. I placed an order with Vans. There closed until Tuesday so a replacement should be here late next week. Better to catch something like this now then after the plane is painted and it comes up during an inspection.