In order to rivet the bracket on to the elevator trim tab, I needed to shorten some of the 3.2mm x 8mm rivets to be about 3.2mm x 5.5mm. The instructions said that I needed to shorten ALL of the rivets that join the trim tab to the piano hinge, but luckily for me, there was plenty of space with the 8mm long rivets. I used the dimpling press, with the dies taken out of it, to push the mandrel down and out of the rivet itself. I then turned the mandrel around and shoved it back into the rivet so the rivet didn't deform when I was cutting it. I cut the rivet with a hack saw (the mini-bolt cutter I was using deformed the rivet too much). One time, I cut through the rivet and mandrel and the other two times, I just kept rotating the rivet around the mandrel (I only did 3 rivets...so far). I don't know which way I like best, but it seemed easier to rotate the rivet. Once the rivet was cut, I pulled the mandrel out, slid it back in the right way, and tapped it back into place with a hammer. I put the head of the rivet down on a vise that was partially opened to allow the mandrel to slide through. It didn't occur to me to get pictures until after the fact, but hopefully the description will help future me (or someone else). In any case, it seemed to work - the rivets still fit in the 3.2mm hole and they are holding tight to the bracket that the trim tab motor will eventually be pulling on.