If they're anything like Cougars of that generation the red part is a translucent outer lens, and inside there's a "clear" fluted diffuser to spread the light. LEDs will have to be custom laid out regardless but projecting them out of a clear non fluted lens is key, LED bulbs don't work right in stock incandescent housings well.
Better option IMO, disassemble the housing and either paint the dull silver part white or laminate it it with chrome foil it increase and even out the light output with the existing bulbs and arrangement.
And Dated? who cares! Your car looks better than 95% of the cars available off dealer lots today.
Last edited by XR7-4.6; 01-26-2016 at 10:27 PM.