There are probably 10,000 different ways to route wiring in an aircraft. At some point you have to decide this is where and how I will route the wires. So the wiring from the back of the aircraft runs forward to the firewall, into a conduit and up to about level with the panel. The next step is to figure out a routing that is maintainable and doesn't add five pounds to the aircraft. Here is how I did it split over several entries
There are two ribs that run from the firewall to the subpanel. No matter how you slice it the wiring needs to get through or around the subpanel to the instrument panel. I fabricated and installed an avionics shelf that is attached (hinged) to the bottom of those ribs. So the best plan I believe is to run to the outside of the ribs and under the subpanel. To make sure the wiring was protected and secured I fabbed two clamp supports and riveted them to the ribs; one on each side of the aircraft.
The images show the support and the Adel clamp attached to the left rib, of course the other rib has one as well. This creates a wire bundle that runs parallel to, and about three inches away, from the firewall. More images later. The large white cable snaking through the images is the Dynon network cable. I have to move that so it is just laying in the way right now.
Clamp support
Clamp with right side engine sensor wires (EGT, CHT)
