I am changing the gears in my 12 bolt (3.73's to 4.88's) and am also having a custom drive shaft made to hold 1350's. The shaft is already at the shop as they were going to use it as a model for the new one. They gave me a call saying that (because it was lifted) it was not far enough into my transfer case (slip yoke) and that they wanted me to take a measurement for the new shaft instead of using the old one as a model. I need to install the new pinion yoke before I can take the measurement. So I install the pinion with the new sleeve/nut/seal/yoke. I know that to torque it you need to begin to crush the sleeve and then carefully measure the running torque as you are torqueing. I also know that it takes roughly 300 ft lbs to begin to crush the sleeve. What is the expert opinions on holding the pinion from spinning while torqueing and what are you guys using to torque with (cheater bars?)? I really want to get the measurment to the shop before totally installing the r/p so they can get to work finishing my shaft (or is this wrong?). I have heard of using the same thickness of spacers as the old gears as a starting point before having to tear it down the 10 or so times to get the proper pattern. Is this what most people do? I think that if I torque it until the crush sleeve is staring to crush and then take a measurement for the drive shaft it will be close enough for the shop to make the shaft. What do you think? Sorry for all of the questions at the same time. This is not my daily driver, I want to do it myself, I am not going to upgrade to a 14 bolt (yet!), I have done this before (once, years ago, with much suffering), and I would really appreciate your expert opinion.