1 leg or 2?

Hey I have a 92 Yota
Is the stk rear LSD/Posi?
If not how hard is it to upgrade?
Any suggestions?
Thanks

Detroit makes a locker. I know my uncle had one in the storage bin at one point. I've yet to find it.

You can alwayas weld the spider gears together to make it a positive traction but the tires will chirp when ya go around corners.