i bought the long tubes too and also had the same leaks. i just tightened the bolts at the header and that fixed that one. as for the collector, i bought a 2 bolt flange metal exhaust gasket and put it in there. worked for about a week then blew the gasket and the leak came back. bought the copper spray and a new gasket and that seemed to fix it. now i just have a leak after my right side muffler where its welded. i took out the metal o ring at the flange.