I'll see if I can find some more Information....but I'm thinking that the 67 harness should be ok. Also check out
www.fomoco.com if you really want the 68 harness. Just look under the parts dept. Myself would probably throw the 67 harness under there...provided its in good condition. When I had my 68 I don't remember the harness being much different then my 66, except for the options on the 68. If your options are the same as the 67 then your good to go. Or lack of options rather. Hope this helps.
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1966 Baby blue Coupe, 289, Manual 3-speed, Edelbrock 650, Flowmaster 3-chambers, and minor upgrades. Interior work includes custom paneling, custom dash dress-up(I refuse to cut anything out of the original), Rewiring most of the electronics, Porsche 911 seats installed soon, and Stroker kit when I get to Texas. November of 2001 I will go back to Dallas.