7 man mechanics. I am an R, 3rd year, but was an L for 20 years. I also am an S on a college crew. As an R, my crew had a playoff game where the coaches requested a 7 man crew. I used to HS B's that had also worked as a F & S on a college crew. We didn't miss a beat. Last year, I worked as an S in a quarterfinal 4A game. The F was also an R. We were out of position as listed on our profile, but we had both worked deep wings in college. In most chapters, it shouldn't be that hard to find an F or an S that has worked the position before.