With the port wing jigged-up on my engine hoist and shop stands (setting the sweep, dihedral and washout). I Started work on the port wing root. I used my new Milwaukee 2" metal hole saw to make the cutout in the rear spar root for the folding mechanism. The new saw worked great, far surpassing my hardware-store bargain-table saw. I cleaned up the slot with a fair amount of filing and will eventually prime and paint the root to match the white fuselage frame.
I then drilled each of the 8 spar root doublers (#30 bit) for the 4 BSPQ-44 rivets that attach each of them to the top and bottom of the spar roots. Then I laid out and drilled just 2 of the top doublers for the AN5 bolt/pin. After checking the fit, in turn, I secured each of the top and bottom doublers to the root end of the spars, drilled and clecoed the doublers in place. Once the new lift strut doublers arrive and I install the lift & jury struts setting the final sweep, dihedral, and washout, I will drill through the upper doubler and root mounting lugs; remove the doublers, deburr, prime and paint before final reassembly..
I have some questions about the but rib closeouts, flaperon cables, Oratex wing covering and trailering the folded wings. I'll post these in the DISCUSSION section.