Tach. Problem

Hi, after 2 days of researching and hands on searching. I cant for the life of me find the "tach terminal" on my 1996 Chevy S10 Blazer. It has the V6 4,3L engine. Can anyone.....ANYONE please tell em where this freakin terminal is? I have searched high and low and studied my Haynes service manual for hours on end trying to find this terminal, and I still cant find it. :banghead: PLEASE!!!!

The factory tachometer reads off circuit #121 (white wire) from the ignition coil terminal "B" to terminal "8" of the instrument cluster.

The tach is read through the BCM via input from the coil...