I took off the snap ring, pressure plate, clutches and frictions. I compressed the return spring module down and removed the single snap ring. I put the double wound snap ring on, and this time it seated correctly. I measured the outer snap ring, and found it's at .076". I re-installed that snap ring and measured for clearance. According to the ATSG manual, I need .075" to .152" of clearance with the 5 clutch/friction set up. With my .076" snap ring, I'm only currently getting .020". It looks like .060" is the thinnest snap ring I can get, so that will put me at .036" of clearance. Close enough? Maybe machine down the pressure plate .045"+/-?
It looks like the clearance really matters at the rear clutch, and I'm good at .046".