Need a question answered ASAP

[GMC Guy]

i found a 12 rear end with 3.73 and limited slip on craigslist today for $200. it's out of a 78 4x4 blazer. i'm about to go take a look at it tomorrow with cash in hand. my question though is, this axle will swap into my 79 2wd correct? dumb question i know....but sometimes when you find a good deal, you get tunnel vision haha

here's the add for reference
http://sfbay.craigslist.org/sby/pts/1745637367.html