Jon, most of the frames are actually white metal castings that I painted and weathered to resemble real wood. But in all cases - wood or metal - I deliberately "sloppily" painted either white or black paint in the area where the decal would be placed. First, I wanted it to appear as though all equipment was purchased as used equipment from other roads. So the original reporting marks had been hastily (and none too carefully) painted over and replaced with the OVT&L's marks. But, second, I figured the little patch of paint would help the decals adhere better to the surface. If not, it wouldn't hurt anything, anyway. It seems to have worked.