I used the the Stuart Systems Etch to clean the skins and stiffeners instead of M.E.K. or Colman Fuel. Hope that's OK.
Image 1 shows the line of rivets taped in. Image 2 shows the stiffener locations taped off with electrical tape and the stiffeners just sitting in place. The tape is about 1/16" from the stiffeners. Image 3 shows the first 2 stiffeners riveted and Pro-Sealed.
I only did 2 to see how the whole process went. It went fine and I'll do the rest all at once.