F25-01R Right Hand Aft Side Panel.
Today I located the vertical channels #2 thru #5 using the blue lines on the flanges lined up with the pilot holes in the aft side skin, The channels were also located down 1/4th inch from the top of the upper longeron. I then drilled the #40 pilot holes in the channels using the pilot holes in the aft side skin as a guide for location.

Click on a link to view the video: