I had to remove the previously fabricated shelf for the ECUs as it interfered with the GTN 650 location. As the 650 must pass through the subpanel, it's location is the restricting variable. I also do not want to cut the center rib unless necessary. I plan on positioning the 650 toward the bottom of the center panel. The radio is only about 2 5/8" tall. I have roughly 4 1/2" below the center rib that can be used without cutting it.
Fabricated a piece of support angle and secured it in plane with 6-32 hardware and blind rivets.
Next, I marked cut lines on the subpanel. I will now mount the ECUs to the right of center, in between the ribs and forward of the subpanel. They will be located and positioned such that all connectors will be easily accessible on the face of the subpanel.
I then spent quite a bit of time studying the G3X install manual, specifically, the size and considerations involved in mounting other "boxes". The GEA 24 engine interface will now be located below the ECUs and to the right of the 650 location. I only need 6 1/2", and if I favor the right side of the cutout, I will have enough room on the 650. I will also position it such that the connectors are accessible.
The cutout will be reinforced around its perimeter using 3/4 "x 3/4 "x 063 angle.
