i think a simple way of wiring it would be to use the wires that powered the spoilers brake lights to power your other third brake light, mounting and all that i dont know about

doing the wiring that way would make it easy because it would light when is needed and not light when not needed

98.5 Black SE ATX S&B filter, SVT MAF, optimized SVT TB, mesh grille, removed orange reflectors, painted rear reflector, gutted pre-cats, optimized SVT LIM, 19lb injectors, resonator removed cant afford an svt but lookin for 1 in nc