I have been working on A Pacific Aeromodel Gee Bee Y 1.20 ARF. I have been having a heck of a time centering the engine in the center of the firewall. Hence, I have removed the engine as I had it mounted, somewhere off center, plugged up all of the holes in the firewall and am beginning to start over. The instructions in the manual say to mark the center of the firewall and then go 5/16 above and 5/16 to the right and use this as a centerline. This sounds good, but as a backup I went to the website and looked at the instructions posted there. There is no mention of this second marking of the firewall. I'm hoping some of you can walk me through this procedure step by step. I'm having trouble finding the center of the firewall seeing that it is round. Pictures will be a big help. I am mounting a Zenoah G-26. Thanks, Aframe2