The Stovebolt Site Forums The Shop Area The HiPo Shop Can I change the gears to Posi?

I have an open driveline rear end gears. 1956, I think, It feels low, like 3,9 or 4,10 gears, but can I make it positraction? Or must I replace the entire rear end. I kind of like to stick with the 6 lugs wheels, and drum brakes are ok. then I dont need to change the front to match.