I decided to hold off on the fan until I research replacements. The fan will come on as soon as the avionics master is turned on. I want to find a similar replacement as a spare or buy two new fans that match. One for the aircraft and one for the shelf as a spare.
I did decide on the location for the ARINC device. I marked the location for the mounting screws and drilled, cleaned up and mounted nut plates. I have also decided to mount the canopy release in the same area. It won't be an emergency release, just a way to remove and reinstall the canopy. It will mean shortening the rod and installing a way to immobilize the release, probably an Adel clamp. You can see the opening in the sub-panel just in front of and to the right of the ARINC device.