[Navy Lifer]

Nothing wrong with OE--ARP is good, but probably overkill for street use.

LH thread, correct

14066913 B BOLT,RR DIFF R/GR(7/16-20X7/8)(HEX) (item #8)

14066913 replaced by 12479028

(info from GM Parts Direct - reference only)
GM PART # 12479028
CATEGORY: Ring Gear Bolt
PACK QTY: 5
GM LIST: $4.08 (per bolt)
OUR PRICE: $2.37