Removed the LE assembly from the cradle and placed it on the spar. Put clecos through the spar into the ribs. Placed W-408-1L inboard rib inside leading edge to mark with sharpie the rivet holes using the leading edge skin as guide in order to provide estimated location of flutes in flanges. Flutted rib. Placed rib back and back drilled the rear flange from the spar and cliecoed it in place. Marked a line on the W-423 Joint PLate 1/2" from the edge. Aligned this line to match up to the holes in the LE skin, leaving 11/16" exposed to support the tank skin. Worked the W-423 Joint Plate into place between the W-701 LE Skin and W-408-1 LE rib. Re-checked position of the LE rib by measuring from the edge of the joint plate to the web of the rib. Match-drilled the holes in the rib and joint plate using the LE skin as guide.
Installing and aligning Leading Edge inboard Rib
Back drilling aft flange using spar holes as guide
Match-drilling joint plate and LE rib using LE skin as guide