The shop heads looked good. I riveted the rear spar and used the squeezer for those rivets. I noticed the rivets seemed to short. But the next longer size was too long. So I used the called out rivets from the drawing and squeezed them pretty flat. The are a little lower than the gauge and not quit wide enough per gauge. But they are per engineering drawing and plan. At first I put the shop head inside the wing, but, I had a little trouble with the rib flanges moving away from the spar when I squeezed them. So I put the manufactured head inside the wing on the rib flange and squeezed from the rear spar. This allowed me to put much more pressure on the rib flange to hold it up against the spar. Worked fine. The few rivets that I thought pushed the flange away from the spar, I drilled out and replaced with rivets pushed from inside the wing.