Thanks to Tim E I have some set-up bearings to finish this up. Of course, it doesn't just go back together easily. My original trac-loc case has .049 on the bolt side and .040 on the tooth side (I assume this includes the .015 for preload as well). I started by putting the case in bearings and cups and all, without any shims to see roughly if the total amount of shims what amount of spacing was needed for zero preload - seems to be close enough around .080. I then removed and reinstalled with the shims as before...It was a lot of dead blow hammering to get it in and when it was eventually in, there was no backlash - it was too tight. Then trying to get the case back out was a complete PITA...I was about to give up. It took a lot of hammering on a small prybar to get it out, and when it came out, there were some metal shavings from the little circular edging at the ends of the carrier tubes. So I kind of feel like the preload was a bit too much - but my .080 measurement above suggests it shouldn't be. And of course I am going to have to increase the amount of shim on the tooth side to create some backlash. If I moved .010 shim from the bolt side to the tooth side, that would roughly create a little over .006 of backlash, but I think I would still have too much pre-load (or maybe I need to remove a bit of the preload just for set-up to make it easier to get in and out, and I can add it back in at the end). After re-reading the FSM, I think I may want to re-check the gaps with a better proceedure as I may not have taken the .080 correctly...try again tomorrow.