Ordered it Thursday night, and it came in today (Monday)! I couldn't believe it!
Thanks to the extensive homework I did here before I even ordered it, I had the old crap out and the new 16612 installed in about an hour! I used some 6 inch wheel ramps to help out, but no jack needed.

This thing Howls! A little louder than I expected, I admit. Virtually silent through 1600 RPMs, then it starts to scream around 2000.

Not sure about these clamps though, I like the look of those stainless band clamps someone here has, might swap them out.

Also, how do I know there aren't any leaks? Should I even be concerned?

THANKS TO EVERYONE WHO HAS EVER POSTED ABOUT THE 16612 INSTALL!

Nothing like the pride of doing it yourself.

I'll get the obligatory pics after I wash her up.

 

Great job! 16612 rocks! You will get very used to the sound after a while and will seem quieter to you than it really is. Mine seems very quiet now until my wife gets in it a rips up the street that I am reminded how awesome it sounds!