Phew! Glad that is over! I hate taking a grinder to shiney cowl. This is what I ened up with. I had to cut alot more so I could manipulate the cowl to get the pipe threaded on. I finally got smart and put some tape over the painted head but not after I managed to scrape some off. I used a whiz wheel to cut a hole and then I shaped it with a grinding stone, I used one for sharpening chainsaw blades, it is small in diameter.

Yeah 10lb. into a 5lb. paper bag, I was expecting to hear a crack any minute! At one point I had to unbolt the engine through the cowl (Luckily I had one nut on) and remove the engine to get the cowl off. Tight fit!