OK. The first time I made the trim tab, it went great. My first attempt turned out perfect, I was a little proud because most builders make several effort or simply use riblets instead of bending the tabs. Doing it the second should be easy right ? Well, I messed up by not checking the outer bend in relation to the outer hole for the horn. To my knowledge one cannot have a flush rivet on an outside corner. So after a large piece of humble pie, and before crying myself to sleep, I ordered a couple of new tab skins and more pie.
No pictures, remember I said I was humble, not ready for public humiliation.