[Ironangel]

Originally Posted by mrobvious34

The cast number on the center housing on mine says GM66. And now that i think about it, the axles appear to be original and they are 5 lug, a 67 should have been 6 lug. Another indication that it is indeed a later one

If your pattern looks good, set the pinion preload
and then the backlash. Setting the pinion preload can be tricky, you need a dial inch pound torque wrench. Holding the yoke while you make slight increases in tightening the pinion nut until you reach 13-15 inch pounds of preload which is resistance. It's very easy to go to far so once that nut gets tight you still have to crush the sleeve about 3/32" more to achieve the correct preload. Then set the backlash...Did you get your initial backlash of .006" using the cast iron shims? It would be surprising and a stroke of luck if you did, thats why I suggested the Super Shim packs, they allow any thickness sandwiched between two thick protective outer layer shims allowing you to tap the shims in place with a nylon or hard plastic drift. Getting the carrier tight minimizes deflection under load. I actually take a preload measurement of the carrier by adding 10 -15 inch pounds to the pinion preload to read anywhere between 20 - 30 total inch pounds on the 12-bolts. Hope I didnt overwhelm or confuse you, sounds like you have a good handle on the situation, good luck. Axle width is 55.5 wide with 30.5 long axles on the narrow rear end. And
axle width is 57 wide with 31 5/16 long axles on the wider rear end. later rear ends...