If it's like PD said about Ricks' tank, they were using my exhaust to do it with! I ended up taking a jigsaw and cutting an end out of the can to be able to get it on the horn of my anvil and straighten it. When I was done, I inserted a disc and brazed it in. Braze is a funny thing. The cap brazed beautifully. Just played the heat and it flowed right around. I had minimal polishing, and it quite nearly looked as if I never cut it out. The header tube on the other hand......!
The header tube had been brazed. Seems to be by simplex as the other tubes are brazed as well. but it was cracked around it so I thought I would touch it up with some more brass. No way! It popped and sparked and fizzled. So I back-up and just took the tube right out. Then made a new one. The can was fatigued considerably hence the support ring. I bolted everything in place to tack it in position. Then went back at it with braze. Much better.
Here are the before brazing pics. But the exhaust is under paint and drying as I type. I will be running some Kerr style chrome exhaust tips.