The reason is a part vanity-matching colors and a part to build a dedicated 'trainer tire' rear wheel so I can free my polished silver alloy Chorus hub from current full time trainer mounted duty.

And I right now don't have a large enough caliper to measure and I don't quite trust myself whether I'm measuring correctly.

You bring up a good point though. I'm not sure whether it is a good idea to "break up" a good Excel built OP wheel for this experiment (since I'm a novice). The other is Performance built OP wheels that I wanna extract the Silver Record hubs for Nemesis wheelset build.