Now we start getting the motor mount on the motor. I'm using 6 8/32 X 5/8" long socket head cap screws to bolt it in place. The mount is turned from a 2" thick piece of 2024 aluminum. It is 3.812" in diameter. It needs to be 2" thick because the muffler is mounted directly below it. The mount has 4 1/4"-20TPI screw threads for the firewall.