Drilled the firewall fitting spacer to the firewall. Painted primer on the side of the spacer that rests against the firewall as a barrier between the aluminum and SST. Installed the fitting in the firewall and applied blue loctite to the threads. Got the needed 45 degree fitting to replace the 90 from a local aircraft parts supply house - like having Aircraft Spruce in my back yard at twice the price but no shipping charge - so I'll need to use them sparingly for things such as this that were holding up my immediate build plans.
