Please help!! Quick Question about axles.

    I have an '87 K5 Blazer with a 3:08 rear end which has gone out.  I desperately want to replace both axles with 3:73's, but have been unable to find any used for a decent price.  I have found a 3:08 out from under a '79 half ton 4x4.  Will the rear housing from a '79 4x4 fit under my '87???  I need to know pretty soon because the guy with the 3:08 is about to get rid of it. 

                   Thanks for your help
                   

All I can say is probably. Just take a measuring tape and check your measurements to the spring and shock mounting areas, measure the yolk to be sure the driveshaft (u-jont is the same size).