[Green Machine]

I guess I wouldn't bother changing the rear in the blazer, you will have to deal with the 8 bolt wheel problem. We bought a Dana 60 posi with 3.54 to replace the Eaton 4:10 open unit in our C20. Since the highest ratio in the eaton is 4:10 and many had 4.56, the Dana is the best way to get a decent rear ratio, and many came with posi also as a plus. Check the ratio in yours, and list it for sale.