While checking VAF, saw the Service Bulletin from Van's Aircraft 16-12-16 regarding RV-8QB Missing Center Section Bolts. Several field reports indicate some RV-* QB kits were completed/flown missing bolts called in in the manual. These bolts are inserted in the forward main spar, six per side.
I certainly don't remember installing these bolts, so a check today reveals 12 holes. I have exactly 12 AN4-11A bolts.
The bolt is inserted from the forward side of the spar cap, the washer and nut is installed from inside the spar box, which seems challenging. I made a temporary tool for holding the nut and washer so I can get them in the bolts, and snug.
The control tube for the forward and after sticks must come out due to the location of the inboard holes.