Finished up these access panel openings. I riveted the nut plate flanges on wet with pro seal, then made gaskets of pro seal with turtle wax and Saran Wrap as a mold release. I let these sit for about 3 days before pulling them apart and cleaning them up. there are some streaks in the pro seal where it evidently didn't completely mix, which is odd. This came from a sem kit and I mixed the snot out of it and shot it out onto a piece of cardboard and then applied it with a Popsicle stick. At no time did I see anything that would indicate it wasn't completely mixed. The sem kit was in my tool box in the garage one rthe winter and went through several freeze/thaw cycles, so I don't know if that has anything to do with it. At any rate, It looks good enough for gaskets, I'm just glad it wasn't a fuel tank.