I'm redoing and existing outdoor lighted 2 sided acrylic church sign. I have the vinyl complete but we are having a problem with the white paint looking brown when the lights are on. It's a rectangle with an oval logo so the four edges have to be painted so you don't see the lighting inside the sign. I have painted the inside of the panels twice and both times it looks brown when light shine thru. Our next step is to paint the panels black in those areas so no light will shine thru. Any suggestions?