No 71 Camaro, (or Firebird/ TA for that matter) had a 12 bolt from the factory regardless of performance option package or trans. 100'% across the board 8.5" 10 bolt.

The '71 Nova did not have the 8.5 rear end. That was not used in the Nova until '72. The 8.5 was not used in the Chevelle until '73.