I started each of the four plates by cutting a length of 0.090 aluminum from the strips I had previously ripped on the band saw. Next, I filed the two long edges to get 3-3/8" inches. With this done I simply measured and marked the remaining cuts. These were then cut on the band saw. I filed and sanded the edges to get the final outside shape. Once all four were ready I started to layout the 3/32" pilot holes for the rivets. This was straight forward and I drilled most of the holes in the drill press.