A few T221 questions

[Short 3/4]

I’m in the process of going through and rebuilding my case. I paid the big bucks to have a “professional” do it a few years back, but that didn’t really work out well long term. I’d really like to get it right this time, so have a few questions:

Much has been discussed about gear movement on the idler shaft. I have two cases and both have side to side movement of the gears that is not the shaft itself moving, but a gap between the gears and spacer. Chaparralman verified that in his unicorn NOS case that there is zero movement of the gears. On both of my cases the idler shaft bearings were pressed on until they were flush with the ends of the shaft. It looks like they should have been pressed on until all slop was taken out between the gears. This would leave the end of the shaft sticking out passed the bearings, but should not interfere with the shimming of the end cap to adjust preload on the bearings. Could this be the reason I and apparently others are seeing this problem?

I plan on running synthetic gear lube when I finally get this thing working right, and in talking to Redline they suggested their 75w 140 NS GL-5 gear oil. Not only should it help preserve those hard to find gears, but they say it should help with noise as well. I imagine the 140 weight rating would also help with the high heat inherent with these boxes. Anyone else using this product?

To keep all that expensive synthetic oil in the case where it belongs, I’m planning to use doubled up high temp yoke seals as recommended by Torque King. They say you can either install them both seal side out, or with the seals facing each other. Would seem like having the spring side of both seals facing “in” would make the most sense. Opinions? Also thinking that a thin coat of gasket sealer on all shims and the splines of the yokes would help prevent leaks. If I dry fit the shims to adjust play, will a little sealer applied on final assembly mess with my measurements? What would be the best sealer to use for this?

I’ve always farmed out gear work in the past, so this is all kind of new to me. Thanks for any and all advice,
Tom