OK, so after trying to find a part that Arrow doesn't make any longer - the midpipe is a thing of the past. I mean, I found a guy in California, but he wanted to charge me another $200 for something I supposedly had already.
I returned the Arrow slip-ons to the DucShop - and went online. I found a Termi half system for less than I paid for the slip-ons! Woot!!!
So, now it's on... the pipes took me all of 34 seconds to get off, and about 20 minutes to put on. But, the on doesn't count against me... Evan wanted to do it himself (drinking beer)

It SOUNDS fantastic!! And, now the bikes are closer to matching than before.