Not to be nit picky but LED's do need resistors. The after market units you are mentioning have them already is all.

LED's are current driven devices. More current = brighter. The dimmer simply lowers the current to the LED.

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1985 300D 198K sold
1982 300D 202K
1989 300E 125K
1992 940T

"If you dont have time to do it safely, you dont have time to do it"

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