i LIKE TO PUT SOME INSURANCE WELDS ON THE OUTSIDE SIDE OF THE FLANGE - NOT ALL THE WAY AROUND, ONLY 1/2 " AT THE TOP AND BOTTOM AND SIDES. Then I take them to a shop with a BIG belt sander used for resurfacing cylinder heads and make them flat. You're right about the headaches though. That is why I run split cast exhausts on the street with NO gaskets.
