I have a Raven Inverted Oil system which has a change over valve that needs to be firewall mounted. Using some .070 aluminum sheet, I fabricated a backer plate to mount behind the firewall. I installed some nutplates to accept the valve. The valve is to be such that the center fitting is to be on a horizontal plane with the sump-to-case parting line. This required placement of the valve in such place so as not to interfere with a fuel line and also the fuselage firewall tubing.
