A couple of things I needed to make were the pulley brackets for the flaps and elevator cables. The plans want you to have a perfect fit of course, but not easy to do. The first bracket is a bit too wide, but a washer will take care of that. I compensated a bit too much and the second bracket was a tiny bit too narrow, too tight for allowing for paint. I was able to “massage” it a bit and it's just fine. I left the ends a bit long to allow for fitting to the tubes. The tubes they mount to and the bottom of the brackets are what keep the cables from jumping the pulleys.