hey toastedoats, is the Magnaflow 94805 the right one?
Thanks

im not 100% sure, if you do a search in the 2000 section for highflow cat, you will find your answers.. here is the thread that contains all that I know about it..

http://www.bonnevilleclub.com/forum/...ic.php?t=52522

You'll actually want a muffler with a 2" intake/outlet for the Bonnevilles with the dual exhaust. I'm not sure what it is if you have single exhaust. I do have Borla PRO XS mufflers on my Aurora, but like mentioned, it'll sound different than what a Bonneville will. On my supercharged Riviera I also had Borla but the Turbo series instad of the PRO XS and it was quite a bit deeper sounding, but it was somewhat raspy and popped a lot.
If I had to do over again, I would probably have gone with the Turbo mufflers again. The sound is a bit deeper and not as loud as the PRO XS'* are. It could just be the engine themselves too. the 3.5 is smaller than the 3.8 obviously. hah. I like the refined sound tho.

here'* a clip of my exhaust the day I got the mufflers installed (after they break in they get deeper sounding.)
http://media.putfile.com/auroraborla

And from inside:
http://media.putfile.com/DSCN0518-66

i could be worng, but i am 99% sure that the bonneville exhaust is thicker than the riviera and has 2.25, not the 2.0 that the riv came with

I'm not sure. The 95-99 Riviera, 95-03 Aurora (all engines) have 2.5" exhaust from the catalytic converter to the T-split, then 1 7/8" after the split to the mufflers... The Bonneville should be the same.

me thinks its defferent, someone needs to measure... i can do it tomorrow at work for an SE single exhaust reference, but i remember seeing a riv exhaust and it looked MUCH smaller than my SE

This was pulled from this thread:
http://www.bonnevilleclub.com/forum/...haust+diameter

The quote above was from Silverbullet who measured the exhaust himself. The SE exhaust will be thicker because it'* a single exhaust, not dual. It should still be 2.25" though.