I’m continuing with installing firewall components while I still have easy access
I drilled holes for an Antisplat Aero oil separator near the top of the firewall on the inside of the brake fluid reservoir.
I created a doubler with nutplates so I can attach the bracket later without access to the rear side of the firewall. I countersunk the rivet holes and used adhesive to attach the doubler to the firewall.
I have decided to install two firewall passthrus for the various wires that will need to pass through the firewall. I opted to install these in the upper corners of the firewall.