65 Valiant wagon taillight wiring

Ok all you spark chasers. Here is my dilemma. I have a 65 Valiant wagon. Years ago someone changed the rear tail lights and the wiring to what I have in the first pic. I no longer have back up lights. All 4 tail lights work the same. running, brake and turn signals. I hate the red plastic lens material that they put in my car. I was thinking about changing the outside lenses to the orange turn signal lenses that the Canadian body Ap5 wagon (2nd pic) uses in Australia. My problem is I want the outside orange lights to act as turn signals only. However the brake lights and turn signals share the same filament in the tail light bulb. This magic seems to happen in the turn signal switch. Can anyone tell me how to accomplish this? I want the inner lights to be running lights and brake lights. The outside lights to be turn signals only. Thanks. IMG_20180303_135106822.jpg Chrysler_Valiant_AP6_Wagon_(16933795421).jpg