I'd suggest bolting the caps onto the carrier, and using an inside micrometer to measure the area where the bearing cups are retained. You can use the cap/carrier assembly that's the closest to being round. Also make sure that the threads on the carrier bearing preload adjusting nuts align properly.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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