A fella on here had some pics of an absolute untouched immaculate original '49 1/2 ton GMC which showed that the bolts were painted black.
This truck wasn't his, but he took the time to take some amazing pictures of it that answered many, many questions about details of these trucks. One thing that I gleaned from his pics was where they used masking tape between the interior color and the exterior color.
It was not exactly where the exterior sheet metal met the door lock and hinge pillars. Close, but not exact.
Another thing was how the end of each beltline pinstripe had a rounded end wherever they began and ended.