this is not for a 3rd gen but maybe you can help me. i just bought the 5 inch autogage tach. from summit racing. it came in the mail today. i was looking at the instructions on how to install it and i understood everything except for the green wire. which goes to a coil or electronic ignition. the distributor i have is this http://store.summitracing.com/global...UM-850001R.jpg and i am not sure how/if you can hook up the gauge to it.

it's a chevy 350 in a 70 chevelle that doesn't have a tach allready

 

you should be able to attach the green wire to one of the wires going into the distributor, that would be your coil wire.

 

if he is using that distributor, and the wire he is talking i assume is the signal wire to the tach, he needs to put a female, spade type connector on it, and run it to the distributor next to where the heavy pink (usually) ignition wire goes to the distributor, there is another slot this is where you plug in a tach,

if you don't get it i'll go take a pic of a distributor, use fancy arrows to illustrate