It's not THAT hard to do. Get a FSM or at least the section on replacing the gears in an 8 3/4 center section. Go to Harbor Freight get a magnetic base for a dial indicator, and a dial indicator. Just saying this as you did not say you had equipment. You are gonna want something secure to hold on to the centers when you take them apart to swap the sure-grip into the 3.23 center, I made a fixture that bolts to my engine stand to hold the case while I worked on it. Mark the caps, and adjusters so you don't mix the pieces up between the two housings. FYI, ring gear bolts are left handed thread. I typically check and record back lash in 4 places, mark each point where you measure BEFORE you remove the ring gear from the housing, write the numbers down, these are the numbers you are going to adjust preload to when you reassemble. So long as you are careful and clean there is no reason why you can not reuse the bearings on the sure-grip unit. Reusing the ring gear bolts is flip a coin, local dealer can get them, or Summit, Mancini, Jegs.
