Need to figure out what rear end I have?

[westofb]

I am sure it is on here somewhere, but I haven't found it. I have a 80 chevy truck for parts and the glove box spid lists option #G01 rear axle-standard. Does anyone know what rear axle is standard (oh, yeah, its a 1/2 ton 2 wheel drive, short stepper if that matters....vin CCG14AS172285). I am sure it is a peg leg drive, which is fine for me, just building a cruiser, but would like to know the gear ratio so I can order the correct speedo gears for it. Thanks for any help.