My wiring kit had the unwired headlight plugs and the terminal ends. I had to crimp them myself (don't ask how many times it took me to get them right) If the LMC plugs only have 18ga wires, you might think about getting new terminal ends from an electronics store and putting them on the wiring harness ends and removing the 18ga wires. Any of the halogen sealed beams or stronger are likely to draw enough amps to stress the 18ga wires.

Also on mine (EZWiring) the high beam indicator and hi beam wires were well labeled. Only guessing was which terminal on the headlight was the high beam. Again the answer is test, test and test again.

'69 1/2T stepside, Sea Foam Green, 250 L6 w/ 3 on the tree, not an option on it, in the family since new.