Im putting a tach in my 87 base model camaro and one of the wires needs to go to the negative side of the ignition coil. Which side is negative and can i pick it up some where else?

thanks

 

Most factory harnesses have all the wires installed regardless of whether a optional item is fitted or not
Tacho wire is white ( marked to int cluster from dist in diagram )

http://www.austinthirdgen.org/mkport...ine_wiring.gif

Look for wire under the dash or at cluster plug ( not used )

Failing that, connector is marked Tach on HEI dist cap next to the pink power wire