Your a-arms and sway bar mounts are identical to a regular LS blazer. You have a ZR2 rear axle ( 8.5 instead of a 7.6 ) It should be a GU6 3:73 posi if original. Compare your rear leaf spring forward mounting point to a ZR2 that is different and hangs lower off of the frame to increase ride height.

 

GU6 is 3:42 axle ratio. GT4 is 3:73 for the zr2.

 

Oops ! I got it backwards. Thank you for correcting the information.

 

 

We can't see the parts in question , however, If I were you I would replace everything up front with stock LS parts and don't pay too much attention to what you take off. The previous owner must have just pieced it together with whatever he had around at the time co mingling ZR2 and Ls components ( longer CV shaft,tie rod end, for instance ) That may also be the reason for the mismatched parts from side to side. I don't think you have a ZR2 rear axle since you did not mention spacers and it currently is not 2" wider than the front track width. It is probably a Ford Ranger or Explorer rear, who knows. Stick with it and you will get it back to where it needs to be and you will have confidence that it is correct and reliable again. Be on the lookout for more of this type of repair as you get familiar with it. Life is interesting and sometimes a challenge, but always worth the struggle. Good Luck.