LED question

i am wanting to use a pair of stock led third brake lights from a GM car. but since the light is a brake light only, how would i get it to be a running a brake light? is there something i can put inline with the hot wire that would bump up the power to the led's when the brake is applied? any help is appreciated

i used grand am 3rd brake lights on my toyota for a while..worked good..i just took them apart and rewired them for stop turn and running light..they have 3 bulbs in them and they are cheap as hell.....but to do what you are wanting you just need a simple resistor..its like 5 bucks u can get it from a place called custom classics i think