Watkins had lots of white Great Danes as well. If you have the Ertl GD reefer kit, you could strip the chrome and go with the white trailer. I think the stainless trailers were starting to be replaced by white ones around '71-'72. The Fruehauf pix I have show them to be white, but with the little vent door in the upper left corner of the nose like Ertl's Great Dane kits. Here's a white GD from the '70s with the newer graphics.
Note the eskimo has since rode his skis off the trailer. I think late 1970 or '71 is when he disappeared. Of all the Watkins pix I have, one thing I can't seem to find to confirm my theory is trailer wheel color. I believe the spokes are red, but not sure.