I have this theory that Burgundy's were really done with 'FireGlo' coloring,...when a body (intended to be FireGlo) had prominent or unsightly 'knots' - extra spray covered them. If too much was needed, it was deemed to become a Burgundy.
I have a '75 FireGlo which has a darkened spot in the wood and was covered in a heavy coat. Though It remained a FireGlo since the area was mainly on the perimeter. However it seems a cross between the 2 colorings.
If you look at the Burgundy posted by the OP,...the darkened areas in the center areas of the wood prevented it from being a good FireGlo candidate (possibly following an attempt to make it one).