Had a nice big open space behind the flight displays that just seemed like the perfect place for the dual AHRS unit to be mounted. A great spot, but one thing that I don't want to do during future maintenace is lie head-first down in the foot well to do work.
Next I checked that I could fit the AHRS unit through the hole for the left display unit in the instrument panel. It did, so I decided to make a cutout in the instrument subpanel through which I could remove the AHRS if I needed to do maintenance.
I fabricated a dual-rail mount using two pieces of aluminum angle and fastened them to the forward bulkhead and to the back of the subpanel. I checked that the rail mount held the AHRS properly oriented to the aircraft axes. I fastened four nutplates to the AHRS and use screws through the bottom of the rail mount to secure it.
Maintenance access is through an opening in the instrument sub-panel, The opening is closed up by a two-piece cover which fastens to the subpanel. There are two holes with snap bushings through which the AHRS wiring passes.
