I talked to the owner of the shop where I have most of my work and inspections done this morning. He has always seemed to be a "by the book" kind of guy and pretty knowledgable on these things. He tells me there is nothing in the inspection that requires a muffler in New York. He also said that as long as the CEL and state computer are not tripped there is no reason to fail a vehicle for emmisions so that replacing those 4 cats with 2 high flow cats and running straight pipes will not be an issue at inspection time as long as my CEL is still not lit. I have seen several people here ask and guess about those issues and I hope that is the final answer at least in NY.