55.2-59 Rear axle width

[8man]

I've found 2 rear axles near me, and either is very reasonably priced.

I need to know whether there is a preference between the two:

1995 Camaro positraction with disc brakes

2009 Colorado with disc brakes, but they weren't sure about the posi, I'll have to go check.

Both appear to be about 61" wms to wms. I believe that is about the width of the 57 axle.

The truck will be a driver for fun only, no racing, probably running a 5.3L with automatic transmission.

I know others have gone with the Ford rear axle, but I want to go Chevy.

So what do you think?