unless I am mistaken, this a fantasy sign, no such thing as a real mccoy in this size/style. so its not a matter of knowing what to look for on the sign, its a matter of knowing what is real.
Ask yourself... how would a station use a 8"x18" tire advertising sign? if you cant visualize it, then stay away. try to think of the HISTORY of these items... not just that its a porcelain sign and you might be able to make a buck off it.
