Welcome to the forums and congrats on the Z!
I have the AAM 3" short tails as well on my Z with stock headers, cats, and pipes still; gives it a nice growl with the muffler delete.
Although with coming into a bit of money at the casino the other night, I really want the full ARK exhaust system now. Talk about loud? lol
Enjoy! and Happy modding! Congrats on the move to norcal too!