Are different Campy hubs of the same period (specifically Record 10s, Chorus 10s, Mirage 9/10s in this case) all the same sizes, especially as far as spoke length is concerned? Thinking about swapping out hubs between my OP/Campy 9/10s hub wheels. Novice at wheel building, can I re-use the spokes on the rim, say Chorus 10s hub to re-lace to Mirage 9/10s hub?

Btw, also, what is best way to measure rim/hub to figure out spoke length?

TIA