Removed aft spar carrythrough, but left the side attach brackets in place. Finished drilling all pilot holes for these (only did enough to pin them in place last week during rigging).
Once pilot drilled, I updrilled them to final #30 size. Removed attach angles & deburred all parts.
Riveted the shear angle to the bottom of the spar carrythrough. Riveted the 3/16" carrythrough backing plate to the carrythrough. Installed the carrythrough back into the fuselage and cleco'd the shear angle to the aft crossmember. Cleco'd the attach angles in place. Used the hand-riveter to install the CCP-46 rivets from the attach angle to the carrythrough since there wasn't enough room for the pneumatic riveter. Riveted the attach angles to the fuselage side with the HF riveter, then riveted the shear angle to the aft crossmember.
Spent some time test-fitting the elevator control rod to the idler pivot. Adjusted the hole size in the spar carrythrough to allow full control travel (it was binding on the lower edge of the circle).
Spent some time test-fitting the southco fasteners for the cowl edge. Like some other builders, I discovered that although Sonex doesn't call them out in the plans or use them, Southco makes no-mar washers and pop-up springs for their fasteners. I obtained some with my last order from ACS. Unfortunately, they add about 2 sizes to the Southcos that are supposed to work in the holes, so I did some test-runs. I'm going to have to get two #240 length studs for the lower edges of the cowl. 220's fit fine with no spring or washer, but it's a no-go with those add'l parts in place.