Finished up the F-820 front side skin and began the F-823 side skins. Started on the left. I had to remove the two oak wood spacers that hold the center carry through together. The rivets were extremely difficult to buck. I ended up using a long flat piece of steel braced against other bucking bars. For some reason it worked well on the left side but so so on the right. I ordered another shaped bar. If it proves useful I will redo the right side rivets.