Modified the F-716 inner and outer, left and right seat ribs by adding the Seat Rib Access plate and enlargening the lightening hole. The two inner left and right ribs are called out in the plans and manual; however, the outer ones are a mod that has been done by others and I thought it was a good mod. I spoke with Van's about this first, and they didn't have any concern. The reason for this mod is to be able to attach the control system base to the F-704 Rear Center Section spar and leave it there during assembly of the center fuselage. Otherwise, it would have to be removed to rivet the seat ribs, then re-installed again. It's not so bad to re-install it, but it's much easier to have full access to this assembly during installation due to the close tolerances needed when installing the shims (washers) so there is no play in the movement. Also, later on, if it's needed to remove this assembly, it will be easier to do it as a unit (base and all). That's not possible to do with only two of the seat ribs having Access plates.
