i doubt its leaking from the crossover, since theres no gaskets involved, only a bell-like fit. If anything, the bolts are loose. What might be leaking is a header gasket. The passenger side head is poorly designed when it comes to the exhaust ports. the wall on cylinder six is very thin and gaskets are very prone to blowing at that spot (at least in my case). If this IS the case...i suggest either buying copper gaskets, which can run a bit pricey, or use no gasket at all, and just seal it up tight. I know some people who use the copper RTV by itself for the header gaskets, but i've never had much luck with it. hope this helps.
