I ordered the optional crotch strap attach bracket installation kit from Van's to add more safety to the aircraft. I did the parts inventory and then proceeded to debur the four F-7117A and B brackets as called for in the plans. The crotch strap brackets are riveted in place between the seat ribs and the seat floor already has the holes where the strap protrudes. The F-7117A&B brackets sandwich together with a 3/32" gap where the belt buckle slides in and is retained with a AN5 bolt. I used a piece of scrap 3/32" aluminum as a spacer and clamped the two brackets together. I then slid the assembly down between the two F-716 seat ribs and clamped in place. I placed the seat floor in place verify the bracket assembly aligned with the hole in the seat floor. The crotch brackets are held in place using LP4-3 rivets so using the pre punched holes in the brackets and my angle drill attachment, I match drilled 20 holes into the seat ribs. I next repeated the same process for the right seat crotch strap.
