Stock posi rear end or Eaton Posi Trac?

[dracko]

I drive my truck in the winter and could really use a limited slip rear end for those snow days. Truck is a 1964 with stock 3.73 rear end.

I did a few searches on here but couldn't find much info. If anybody is well schooled on these, I'd appreciate some advice. Like, what is the best option for a lsd swap? How good were the factory lsd units? Are they rebuildable, hard to find and what year posi's will fit in a '64 pumpkin?

Or would it be wiser to just buck up and buy a new Eaton positrac? Will my factory gearset bolt up to the eaton unit?

thanks in advance for any info