ecu wiring

It may be a stupid question but how do you know which plugs are a,b,c on the ecu. All I see is numbers on the 2 black plugs and notta on the white plug. I only have a Hanes manual and its not very helpful.

This little pic at the bottom might help: http://www.allmotorhonda.com/techpages/B-sereies-wiring.htm

the big white plug is plug A and the black plug next to the white plug is plug B and the last black plug is plug C...