Finished the Center Section today except for riveting the left and right sections to the forward and aft center section (see photo three.) The large bolt holes and the two on either side are close tolerance bolts. This is were the wings attach to the airframe. The bolts have to be driven in, yes driven in. It required more force than I was willing to use, so I took a break and checked some forums on Vans Airforce. One suggestion is to freeze the bolts and them put in place. I am concerned about getting them back out, so a little more research is needed. Everything else is done. I started riveting the firewall, but needed a different yoke for my squeezer. I ordered that today. So I should finish the firewall this week. It will only take about an hour to finish riveting it.