So I got a bi-turbo exhaust for my Puch. Sportsbay failed to mention that it was for a Maxi and not my Magnum MK11. So now the problem: I can't get the damn thing to seal. There is a gap on one side between the cylinder and the exhaust. I tried using high temperature gasket material but the gap is still too large. I need a wedge like gasket in order for it to seal. What the hell should I do?