Riveting the rear spar to the wing ribs was accomplished mostly with a squeezer. There were a few places where it was really challenging to fit a yoke without interfering with another rivet shop head or a flange. I found that I ended up cutting a small groove into a few shop heads, caused by the yoke dragging a corner against it. These didn't seem too deep, however, so I simply smoothed them out with a file.
The hardest part of the spar for me was the new inboard aileron bracket from the service bulletin. The rivets along the outboard flange of the bracket couldn't be squeezed because my squeezer would interfere with the bracket itself and couldn't be square. For these rivets I had to use the gun and bucking bar. For the inboard flange of the bracket, the neighboring shop heads interfered with even on offset rivet set. For these, I had to flip the rivets around so that the manufactured heads were on the inside of the spar. I couldn't quite square these up, and the shop heads ended up being