Decided to rodo my manco 573 and started with engine. I wanted a header so I started bending 1 inch. I normally cut out the base but decided to just cut the stock plate off and use that flange. I surfaced the weld and punched the pipe out and started from there. I has an old chrome tip off a hot rod that was 2 inch. I measured half inch and slotted slits all the way around. I hammered all of the slits one after another into a fan which let the I'd of the tip fit the one inch outside diameter the header pipe.