RV-7 QB Wing Rear Spar Trimming
It had to be done on my RV-7 QB wings. I completed this a few months ago.
I did it gradually to avoid initially removing too much material on the spar, cutting outside the lines at first, checking the fit and trimming more as necessary in a couple of iterations. This did require slipping the wings out of the fuselage a few times.
For my QB wings, it ended up at the dimensions shown on the plans.