someday

okay guys i asked this in the integra forum last week and noone could help me, i have a 00gsr obd2b i have a conversion harness to run obd1 but i think the wire for the tach signal is missing i looked at the pinouts and cant find wich wire it is can someone tell me what to connect as far as EX. obd1 a21 goes to b09 on obd2b to make work or can someone tell what the description of the wire is that honda calls it so i can find it myself thanks in advance.