Splicing into 1980 JD Spitfire Brake/headlight WiringHarness

[bplifer18]

I had a broken brake retainer on a 1980 Spitfire that I am replacing with one from a '78 Spitfire. Instead of replacing the wire harness, I am just splicing the wires from the new brake retainer into the '80 wires. I have looked at both specs (wiring diagrams) for the models and the '80 makes sense as far as colors and routing, however the wires on the '78 coming from the brake switch and high/low beam are all 5 black, instead of yellow/tan/pink/green. I tried to match up connectors to see if I could match them that way but the connectors are different as well. I scraped some of the black insulator off the wires as well to see if they were colored underneath but no luck. My last resort was to post here and see if anyone could help. If anyone knows which is the A/B and A/B/C posts on the brake and headlight respectively, as far as bottom, top wire on brake and bottom, middle, top on headlight for '78 that would help tremendously. then I could match it up with the yellow, pink, green, tan on the '80 wire harness. I just don't want to connect it wrong and blow the voltage regulator or something.

Thanks in advance

[harleysportster]

1978 Spitfire wiring..
http://www.jdsleds.com/tech/wiring/70spitfirewiring.jpg
1980 wiring..
http://www.jdsleds.com/tech/wiring/80spitfirewiring.jpg
Hope this helps.