LED wiring.

I was wondering if I wire leds connected to a micro switch what would be the current passing through it and how would I connect it. Would it be POWER and GROUND; SIGNAL AND GROUND, or SIGNAL AND POWER. basically I want the light to turn on when the micro switch is pressed. Would this even be legal?

Sounds legal to me. As a custom circuit, it would need to be powered by a 12 volt branch circuit from the Power Distribution Board protected by a 20 Amp breaker.

Wire the LED, the normally-open switch, and a resistor of appropriate value all in series between power and ground. Choose the resistor value to set the current through the LED to whatever it needs to be.