Lowell, thanks for the kind words and suggestions. Yes, my rubber-cushioned mounting brackets are already separating (one worse than the other). I called my local dealer and they stock them for $20 ea, so I plan to pick up a pair and use one of the old ones for an emergency spare. Like you, I will probably elongate one or more of those mounting holes to relieve the tension on the passenger side.
Just as a heads-up, the additional 1" of case length actually proved to be about 1/2-3/4" more than I actually needed. Alex (the fabricator) did such a clean job cutting the old mufflers out that I'm actually going to re-sell them. But if anyone is unsure, the 1" is plenty and it didn't change the look of the pipes at all.
Sunny and 75+ here today....and no pipes. Waaahh!!!!!