There are a couple of ways to identify a posi without removing the cover. Only one is a positive ID.

1. Find the axle code and match it to posi; won't work if carrier has been changed to non-posi.

2. Look for aluminum tag on bottom right bolt of cover; may be missing.

3. If you can jack up the rear axle and put the car in neutral or drop the driveshaft, turn the rear wheel on one side and the one on the other side will turn the SAME direction if it's posi.

4. Or you can pull the cover.

Did I miss any?