I also started to fabricate the filler for the oversized left wing spar slot. I cut a piece of aluminum scrap to fit behind the right side of the slot. I drilled attachment holes so I can secure it top and bottom. The piece of aluminum will tuck into the corner between the skin and the sidewall bulkhead. I will put some RTV sealant in the corner recess and then slip the backup piece in place. I riveted the piece of side skin I inadvertently cut out the first time. I believe with a little Bondo filler around the edges, after the airplane is painted the patch will not be noticed. Of course I will always know it is there.
After working on the left side I turned my attention to the right side skin. I riveted the side skin in place leaving the areas with blue tape unriveted. I am ready to rivet the left side skin.