Reworked the driver's side cat...quite a bit of obstruction - some intentional and some not, it appears:
Before:
The initial inlet is over 2.25, but it necks down with the sharp tubing ends at 2 inch. So out came the Dremel.
After:
The end result is at least a smooth flow into the cat...can't open it up due to the tubing thickness. Interestingly, the Dremel provided grinding tool didn't get far. However, the Amazon grinders (for $20) did a much better job. In either case, I have metal shards everywhere...including slivers in the hands...and I was fully covered! Unfortunately, I did see more 'melting' of the driver's side cat than I was expecting...likely doesn't help the overall power numbers...