at the shop there is a 10 bolt rear end from a 97/98 s10 blazer that is a factory 3.73 posi disc rear....but i was woundering if it could go onto our cars?..bolt pattern etc..an 89 formy 305 tpi thx

 

Sounds like it may work, but I can't say that i've done it myself. Take pictures to compare side by side. I doubt it's a direct bolt in. You may have to do some cutting and welding so springs and shocks will fit onto the diff. Also, measure width between axles on both differentials. You will also need the calipers, and a different proportioning valve, but from what i've seen online a stock one may work ok.

Now that i'm thinking about it, it sounds like more trouble than its worth. Probably would be easier to do a gear swap and set up your diff. Have someone help you so you can learn how to set backlash, pinion depth, bearing preload, if you've never set up a rear before. It will help you for a long time.

Also, theres some pretty extensive threads on here about swapping a 4th gen rear, which sounds not too difficult. If rear discs is what your after, you may want to look into that

 

Im fairly sure blazers are leaf spring rears.

 

You would need to do ALOT of cutting and welding to put that rear into your car as f-body rears are unique. Also I believe that the limited slip unit in that rear is a gov-lock(aka gov-bomb, grenade-lock). Not the most desirable unit. Honestly I would suggest a new plan.

 

The axel will be to narrow. But if you do a mini tuckand buy some dished out rims it might work. If you can get it cheap and get it in im sure the stock posi and 3:73's will hold up fine.

 

The diff won't fit because it's a different width plus the S10 will have leaf springs and the third gen has coil springs and needs a way to attach the torque arm.

You could probably pull the disk brakes off and attach them onto your 10 bolt. The gears and posi could be pulled out but they will require 28 spline axles. 90-92 third gens have 28 spline axles but aftermarket axles are cheap and better than the factory ones. The S-10 axles won't fit in a third gen housing.