Installed a trailer hitch on my Lesabre and now trying to hook up an electrical wire to the trailer. Does anyone have an electrical diagram and instructions on how to wire a trailer?

Below is how I think the Lesabre rear taillights are wired;

Driver' Side
Yellow = Driver'* (left) turning light
Green = Brake
Purple= Parking/tail light
Black = Ground

Passenger Side
Green = Brake/Passenger (right) turning light
Brown/white stripe = Parking/tail light
Black = Ground

Did I get it right? Does anyone know where I can purchase a cheap trailer wire converter, if I need one?

Do you have the wires installed into the Lesabre, confused. Any hitch shop can help for car and trailer for sure.
A wiring kit for the 03 Lesabre is available. or any trailer set up.

Online E-Trailer comes to mind and they do have a module based wiring kit for the car.
Surely it must come with instructions?
Link: https://www.etrailer.com/t1-2003_Buick_LeSabre.htm

Also found this flat 4 pin wiring information about the E-trailer kit:
There may even be a video on this:
Flat 4-Pole Wiring Harness for 2003 Buick LeSabre | etrailer.com