Those wire colors look somewhat foreign to me.
Usual colors are:
RED - stop/left turn
BROWN - stop/right turn
GREEN - clearance/tail lights
WHITE - ground
I would suggest you use a multimeter to figure the source wires out.
'07 K3500 Silverado LT Crew Duramax (LBZ)
2016 Salem 27RKSS
1984 CHEV SCOTTSDALE K20 2GCGK24J0E1XXXXXX (Chevrolet Legends-Class of 2019)
"...exhaust fluid? We don't need no stinkin' exhaust fluid"