So, I've just lined up and cut the hole in my inboard tank rib, centered to perfection. I then aligned the T-708 access plate with the vertical stiffener bead, aligned the T-407 stiffener ring beneath the plate to ensure the holes lined up, drilled the #19 holes for the #8 screws, removed the access plate and drilled the #40 stiffener ring holes. Then in all my amateur aeroplane building wisdom, decided to countersink the rib and use NAS1097AD3 oops rivets to hold the rib/stiffener/nutplate combination together rather than dimpling the 0.032 rib and countersinking the stiffener plate. Van's says to rivet it now without proseal, but I can see that the tooling hole is in a compromised position (1/64th from the edge of the gasket). Looking on the forum, the suggestion is to put proseal in the hole, however being a Proseal virgin (apart from the trailing edge applications) my question is, should I fay seal the this stiffener ring first, then attempt to wet rivet my oops rivets once this has set up for a day or so, or should I just do it all in one hit? I guess I'm just a little paranoid given that the last thing I wan't in my tank to leak. Also, has anyone successfully used NAS1097 rivets in this application, or am I going out on a limb here? I just thought it may give better sealing than dimpling in this situation.