That movement over your tech mentioned is because of the difference in r&p thicknesses. Yeah, you *could* make it work, by backing the adjustment off on one side of the carrier bearing and cranking in the adjustment on the otherside, to get the right backlash (sometimes even then the backlash isn't right because you run out of threads to adjust). Same can be done on a Sammy using Kick gears (without the spacer), but here's the problem...
The bearing adjusters will be out of thread and will not be fully supported correctly and/or backlash not adjusted correctly, and *could* lead to premature failure of the carrier bearings, R&P or both. This is why the "can & spacer" came out so the bearing adjustment would be correct. Well, the spacer that is. The can simply kept the cross pins in place. XL7 5.12s are thicker (stronger?) and don't need no cans and spacers if used on a Sammy carrier. Yes, XL7 5.12's and a Sammy 4-pin will allow a lunchbox locker.
Additionally, since the axle shafts will remain in the static location, if you move the carrier over to get the right backlash with the new gears, then the sidegears will move onto one shaft more and the other one less. This is why you change out the inner driver side shaft and inner pass CV cup with Kick ones so the axle splines are where they are supposed to be in realtion to the new location of the sidegears.
Ya know, if I had both of these on a bench top so I could show you, it would be soooo much easier to explain and understand.
As a foot note, the GV CV stub is just too short once the Kick geasr are in and the carrier moves over, and a Kick CV is a must. But you can reuse the GV inner but cutting about 3/4" off the spline end since finding the correct Kick inner can be tough (I have 2 extras because they don't grow on trees). Yeah, you lose the c-clip retention by cutting, but since you usually need to wail on the flange with a beat stick to get the friggin' thing outta the support bearing to begin with, I'm not worried it will pull out. Mine never has, and I ain't exactly gentle on stuff.