Thanks for the pic Ross. I'm working toward an opening about that size my self. The angle of my muffler will cause it to hit the firewall so I'm opting for a extension only, no muffler. I was going to install fuel dots in the cowl but now I'm considering putting them back farther in the fuse. Or maybe I'll glue a piece of ply to the firewall flush with the side of the fuse and just have a hole in the cowl so I don't have to disconnect all that when I remove the cowl. I don't even feel like fooling with tonight. I put together a kit quicker than this thing goes together.