As far as I know, it's a given that "engine paint" is 500 degrees. My Bill Hirsch engine paint is 500, even Duplicolor is 500. They do this for the reason you just mentioned.
I noticed in looking over Dennys blue gray that Bill Hirsch's has a blue tint to it as well but not nearly as pronounced. Depending on what kind of lighting you have in the shop, who knows what you are going to see. In any case, everyone can probably agree that Ford Gray is too light.
Tims response to his posted article above really tells the whole story in the clearest detail we have.
