The quote was "$500-600" depending on if they had to fabricate a new exhaust hanger rod or not, to weld onto the system.

Guess we'll find out in the next week how the Flowmaster system with center kidney muffler goes on the E500. I'll post phots during/after install, and do a sound/vid with my digicam.

I'm more interested in a factory-ish sound than something too much more aggressive.

Stay tuned.

Cheers,
Gerry