Thank you 79er. Your answer saved me from buying 3 1/2 inch reducers and finding out that I didn't need them. I'm going to use the extended reducers from Jeg's. Having the size reduce down in 2 inches sounds like it would be more restrictive than reducing in 6 or so inches. I might even get excited and have the muffler shop run 3 inch pipes from the header through the crossmember before reducing it.
If you read that I'm running ten second E.T.s at 140 MPH with my mostly stock L-48 you will know what my secret is. More likely 14's with a reaction time equal to my E.T.