Tape the plate securely to the front of the fuselage. Make sure you align the thrust line marks both vertical and horizontal.

Drilling the firewall: Because you can’t realistically put this in a drill press, I like to use the Harry Higley drill guides to keep the holes square when using a hand drill.

What I did next may seem a bit more complicated than it needs to be, but I’m a stickler for accuracy. I drilled (1) 1/8” hole through all at the top location “D”. I then pressed a 1/8” dowel pin in this location.

Check alignment again and drill another 1/8” hole at either of the bottom 2 “D” locations. Press in a 1/8” dowel pin here. The pins will prevent any shifting while drilling the remaining holes.

At this point, assuming all is still in alignment relative to the thrust lines, drill the remaining holes with a 3/32” bit.

Remove the engine plate and pins and verify that you have all the required holes before proceeding further.