I finally pulled the trigger on a .308 build. After some research, I settled on these components:
20" Lilja 10740 Barrel
Mega Ma-Ten Keymod Upper
Ma-Ten Lower Receiver
Magpul PRS Stock
Ranier Arms NiB Bolt Carrier Group
Geissele DMR Trigger
Syrac Adjustable Gas Block
AAC Blackout w' 762 SD...