Gear Swap on 12 Bolt Axle

[BruthaMan]

Hey Guys,

Been checking out some gear swap threads this morning, but unable to find an answer to some questions I have.

I have a 12 bolt axle on my 78 SWB with 2:73 gears. We pulled the cover off to check. I'm not very familiar with axles, but trying to determine what I'll need to swap out gears.

I want to go to a 3:73 setup (700r4 going in). I've seen mention somewhere before about swapping "carriers." Would that be necessary with what I have? Or do I just purchase the gears and have the shop do the work?

Also, how do I tell if it has posi-traction? Is that something I can check with the cover off?

Thanks for your advice!