I went with an RRA lower and a complete 16" CAR kit from Model 1 Sales. The basics:

16" Heavy barrel / chrome lined chamber bore
Standard bolt carrier group
A2 flash supressor
YHM rear site
YHM free float 4-rail forearm
Sierra Precision grip
Tactical latch charging handle
Large mag release
Magpul Maglevel mags
UTG deluxe foregrip
6-position stock

Coming this weekend... optics (EOTech or Aimpoint)! Now for the first photos....