I'll take a guess, Center High Mounted Stop Lamp
The LED chip is rated for 260 mA but at that current level, the plastic emblem would get damaged - way too hot. I experimented with different values for R1 and ended up with 68 ohms. Best compromise between luminosity and heat. R1 needs to be a 5 watt ceramic power resistor. All testing was done at 14.2 volts with peaks of 15v as this is where most GM alternators have there control voltage set to.
I ground a trough for the wires and epoxied them down. Bits of heat shrink tubing were used, a 2 pin molex connector and everything was soldered. Got to sand the epoxy flat on the emblem backside yet, drill a hole in the fascia, emblem mount area, for the connector to pass thru and wire in the connector to the marker circuit.
Resistor:
https://www.digikey.com/products/en?key ... 5JB68R0-ND