I HAVE A FEW QUIESTIONS IF YOU HAVE A POSI AND DO A BURNOUT WILL BOTH TIRES SPIN AND IS EATON A GOOD BRAND AND IS IT DIFFACULT TO INSTALL A NEW UNIT AND GEARS PLEASE HELP ME OUT MY REAREND GOES BANG AND DOESNT BURNOUT SO I NEED TO REAPLACE IT ANY WAY THANKS

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1 only if it's working
2 yes
3 not really if you have the tools and basic skills, most people lack both

thanks for answering those things i have an other quiestion what else do i need to buy other than the unit it self, and what tools are needed to compleat this job

if you only want to swap to a posi all you need to do is change the ring gear to the new carreir and swap it in, set back lash and check the contact pattern.
if you change the gear set you'd need a pinion setting tool, or a depth mic and something to use for a datum, dial type in/lb torque wrench, ft/lb torque wrench, indicator and base. common hand tools, something to hold the yoke, press, bearing spliter

Do you need someone with a press to get the ring onto the carrier?

Nope, and in fact I'd advise against trying to press the ring gear onto the carrier, because if it gets cocked going on it can screw up the register on the carrier.

Make sure that the back side of the gear and the differential seating face are free from any burs by running a fine file across both surfaces. Then seat the ring gear as best you can by hand. Use two bolts that are about 3/4" longer than the stock bolts to draw the ring gear onto the carrier until you can thread the correct bolts into the holes in the ring gear by at least 1/4". Then remove the two longer bolts and tighten down the ring gear bolts until the gear is fully seated by alternating sides. Then secure the carrier and torque the bolts to spec.