In the second pic you can see I installed a ring former on the inside of the firewall. THe plans originaly called for a 1/4 in firewall with blocks to screw the cowel on but I did not like that . So when I get the main firewall cut out it will blind nut to the ring former and the engine, tank, throttle servo,ignition and ignition battery will mount to the removeable firewall. This way if I need to get into the noe of the plane to make repairs all I have to do is remove a few screws and everything slides out . I have to give Greg credit for comming up with that idea. The 3rd pic shows the ring former installed.
the 4th pic shows all my formers cut out and ready to install.