Decided that I was going to add a skin 'doubler' above rear ribs 1 through 4 to give it a little more structural support where I was going to be walking to enter/exit the cockpit. Had some spare 0.25 6061-T6 for just such an instance. Rough cut it to shape, then I'll slide it under the skin in place and then drill the holes to match the top skin. Then I'll pull it out and will eventually rivet it on top (makes it more easily changed out if needed in the future). The top skin hasn't been deburred yet, so can't really do that yet. Once done, I can slide that wallking skin in there and final cut to shape (before final drilling). I went ahead and rough cut out for both wings. Also, when i was drilling the skin-to-spar the other day, my drill bit seemed to get caught a few times on something. looks like it was the spar doubler nuts. It's probably prudent to replace those now. Have new bolts and nuts on order.