Hey man, there are 4 main wires for your ignition ok?
On your 66 there should be one thick yellow wire coming from the main power to the ignitionswitch, then one that goes to the S button on the soleonoid under the hood(black or blue with a red stripe maybe), and the other (red or pink) should go to the ignition coil, then you should have one black wire with a green stripe that is B+ going to the STUD covered by the rubber nub, which should be hot all the time so watch it back there..
I THINK that's the way it goes
Look at some diagrams....
