Classic/Antique Car Repair: positraction, 1970 oldsmobile 442, bolt posi

Question
hello, i am the owner of a 1970 oldsmobile 442. I recently bought this car and after checking everything out, i discovered the positraction wasnt working. I know that 1970s 442's came stock with 12 bolt posi. The rear end gear box has 12 bolts so i know that it should be what it is however, i know that the posi on my car isnt working, or isnt even there because when I rotate one tire, the opposite tire spins in the reverse direction. (also when burning a little rubber, only one tire spins.) so my question is, is it possable that there was positraction, only now it is broken or worn out? and if so would it yield the results im getting. what are my options to fix it? would i need to buy a whole new rear end, or could i just have a new posi unit installed? . thanks for any help you can offer.

Answer
I'm back on duty again.  I hope you've already gotten an answer from someone else but in case not:

There is no reason to worry about this situation unless it is making bad noises.  Probably someone put the wrong grease in it at one time and the clutches are not catching.  The car will run forever that way - don't worry about it.

If you want to get it working again, my guess would be the easy way is to find a source for an exchange unit - either the center section or the whole rear end assembly.   

Good Luck

Dick