I like to have my amber lights stand out in contrast to the paint. I just used 3 different techniques for some running lights and fog lights on an ongoing build.
I thought I would share them here in case they may work for you.
#1a and 1b Chrome fog lights:
These mount from the rear. I applied an alcohol based artist pen to change the kit chrome to amber.
The fit and/retention location on these is very poor. I used Testors window maker to retain them as it wicks around the perimeter and dries crystal clear.
#2 Cab visor running lights:
These are each supposed to sit into an individual well. This really dulls/darkens the lenses.
I opened up the back of each well and used BMF on the back side of the visor to add reflectivity.
Once in place and lightly held by the BMF, I used Future floor polish to be the "adhesive" and gloss the lenses and the visor.
#3 Side skirt running lights:
Again drilled out the back side of the recess and retained the amber lenses.
However, this time the reflectivity is provided by some Molotow applied to the back of the lens as BMF would be to far away due to the thickness of the part.