I mounted the AHRS just aft of the firewall on the right side - made a shelf attached to the FW bracing and R side panel rib. Location was selected because I had room there and easy access to the pitot & static lines. The magnetomer is mounted just forward of the first bulkhead aft of the rear baggage wall. I made a small shelf that has it near the top of the tailcone - reasoning is that this was the best compromise between access and distance from eletrical "stuff". Ground testing with power to everything shows that it isn't affected by the battery contactor, AP pitch servo or strobe power supply.
Still a few weeks from flying though.
Bob #40105