Cut 0.5 x 0.5 tubing to 13/16" long to serve as standoffs for the secondary ignition coils. Measured and marked their location on the firewall and drilled mounting holes. Spaced lower holes based on lower coil hole location.
Temporarily mounted with AN4 hardware. I'm going to permanently mount them using nutplates, as the hardware on the cockpit side of the firewall will be blocked by the gas tank once installed. Nutplates have not arrived as of today, but should be here very soon.