The template fits nicely, I then transferred the cutout to the metal and began by drilling the curved part using a unibit. I then proceeded to cut the straighter part using some snips and got it to roughly the right shape. A lot of filing and dremelling got it down to the final shape.
Still not perfect, but I will finalize it as I fit the mount. Tomorrow I’ll continue fitting the mount and measuring and then hopefully drill the mounting bolt holes. My goal is to have the tailcone fully riveted by the end of the weekend. Cheers!