Masking tape

I've used masking tape for several items like this including canopy frames.

tape a piece to a hard surface, I use glass, paint it, then cut your desired width strips with a sharp blade. After installing your painted tape strip paint  it with a clear coat like future or clear paint to seal it in.  Cheers.

I use strips of the tan masking tape for seat belts and shoulder harnesses.  The right color for certain era belts, cheap, and self adhesive.  I have either used them with PE fittings, or for smaller scales just paint the fittings on with steel or flat aluminum paint.