First, I studied the ES AIRFLOW FUEL PUMP-1 Installation Instructions to get a good idea of what gets modified and how the system goes together. Basically, the aft 9-1/16" of the front cabin cover gets removed to make room for the fuel pump and filter bracket. Two screws on each side of both the cabin cover and bracket secure them to the floor stiffeners. Large notches are cut in the aft end of the cabin cover and the lower end of the fuel pump cover to make room for plumbing. The pump and filter will mount via band clamps through pre-punched slots in the bracket. A "doghouse" style cover will extend from the fuel valve cover back to several inches forward of the joint between the pump bracket and forward cabin cover.
I trial fit the F-7115 top and side cover parts and marked the longitudinal positions of F-782C/F-7115A attach screws on the F-782C (photo 2). My plan is to pilot drill #40 the two forward screw locations on each side through the floor stiffeners and F-782C to ensure that the F-782C is parallel to the bottom skin and is set at the correct height and longitudinal position, before trimming the forward end to make room for the F-7115A bottom cover (fuel pump and filter bracket). I plan to drill the aft four screw locations after fitting the bottom cover.
To accurately set the 15/16" height of the forward end of the F-782C, I used two pieces of 3/4" square tubing with 3/16" drill bits taped on them. The height of the aft end is set by the attachment holes to the F-983C fuel valve cover. To ensure that the vertical position of the attachment screws through the floor stiffeners is accurately set, I fabricated a jig by using the drill press to place a #40 hole through both sides of a piece of 3/4" square tubing 11/32" down from the top (photo 3).
Fuel pump and RV-7 installation kit.
Pump cover looks like it will fit well.
Jig for drilling floor stiffeners for screw holes.