So im installing my shackles tomorrow, just to be clear do i take off the stock shackle and put this one on or do i put it where the leaf spring was and put the leaf eye in one of the holes? pretty sure its the first one.

 

Swap it. Old Shackel off, new shackel on. You may have to lube the bolts with penetrant. An impact gun is recommended. Use some antisieze on the new bolts. Did you get new bolts? You should as a back up, the bolts are notorious for being seized up. You might have good luck in Alabama with reduced corrosion rate.
A longer than stock shackel will give you some lift and can be used also to change your rear dif pinion angle (tips pinion up) if you are looking to improve driveshaft alignment. So basics are its a swap, use penetrating oil, impact gun will help.
Best of luck

 

Yeah thats what i figured, I pb blasted it a while ago, Gonna before bed and tomorrow morning. They dont look to badly rusted, but yes the kit came with new bolts,