Your car is 26 years old. If no one changed the hardware chances are the springs are rusted or broken. The cable is probably shot too. You can try it but these brakes were never too good to begin with.
I have rebuilt several with new ss parts,steel shoes,and new rotors and they still don't work good. The last set I did I adjusted the braeks with the T arms on the bench. Installed on the car,installed new cables, adjusted them until the rotor locked up then backed off 10-12 clicks. Rotor spun free drove the car and the spindle and wheel were pretty hot. Backed off the shoes completely and let things cool down and tested again- no parking brake but no heat. I didn't have it in me to jack the car up again and go back to adjusting them.
Good luck. If the rear rotors rivets are still there then you have original parts.