Started by cutting the angle for the inside tank nose reinforcement and attach bracket. Did this to get scrap for making a pop rivet jig. But after cutting one of the flanges to the measure shape, decide there was not enough material to make the jig. So found some other scrap, cut it to size and made up the jig, as featured here. Mines not as nice, but it worked fine. This is needed because the holes are too close to the bracket webs, so the rivet gun can't get the right angle to properly set the rivet. The jig allows the gun to be at an angle for clearance, but the rivet is pressed flat into the hole. The pop rivet shaft bends at the jig, but that's not a problem. This all took an hour.
Next used the jig to pop rivet the tank attach brackets. The jig is easier to make than defacing the pop rivet gun! After setting two rivets, decided to match drill all baffle to rib holes. Marked the two that were already riveted to do later. One builder forgot this till later and had a messy recovery.
Finished all the pop riveting and then trial fit the tank. It sits on fairly well. Just about a 64th gap on the upper outboard corner. Took it off and fussed, reseting the outboard tank rib. There is also a slight mismatch in the two leading edge skins right at the nose. I think the tank skin isn't shaped to the rib quite as well as the thinner outboard leading edge. This leaves a small gap between the upper leading edge skins, and the main skin. All the other joints fit perfectly.