Replace your 66 Chevelle's old conventional dim bulbs with Hitech?s LED conversion. You can still retain the factory taillight look when converting the old conventional bulbs to Hitech LEDS. LED conversions are simple to install with no modification what so ever and you can utilize the original bayonet style socket assembly housing and lenses. LED?S are very efficient, and are rated to last 100.000 hours. Each taillight is fitted with 87 super bright hi-intensity wide viewing angle LED?S. The appearance of original look will not change, but taillight intensity will be brighter. Note: Taillight housing and lens not included.