Because I installed the diagonal supports (per the photo guide) before putting on the attachment points, my top rivet on the diagonal did not match with the size of the specified part. I spoke with Travis and ZAC and asked if I could widen it, which he said would be fine. I made two new parts, adding 5mm to the aft edge so I could pick up that rivet hole. Success.
Attachments in place
Close up of front attachment -- widened to pick up diagonal