Today was right side flange installation day. The flanges have been countersunk so it was time to lay them out on the top skin and properly space them to allow for the lower flange to be adjusted so as to be in line with lower cowl Skybolts . The spacing proved to be just slightly less (about 3.3") than the suggested maximum of 3.5 inches. All the flanges were also spaced 1/4" forward of the forward edge of the skin. The flanges were clecoed as I drilled thru them and the scrap metal vacuumed to avoid contaminating the engine any more than necessary. The lowest flange (blue taped) is undrilled and trimmed to avoid the vertical hinge. Now to do the left side before aligning the lower cowl. I did notice that the lower cowl vertical hinge pin may have a problem being inserted behind the lower flange, but I'll have to wait and see how things work out. There are options - I hope. Riveting will come later.