It is the same grill....
I didn't realize when I was trying to get the same camera angle when hot that I put the lid on facing the other way.. DOH!
The later reds (90s era) do darken when hot, but it seems to take much less fuel to darken the reds of the 1960s and 1970s. The one above was chugging with a half full chimney load (full size chimney) of charcoal. My 1995 EO red takes an over flowing full size chimney to even get half as dark as this one above, or my '79 red, or my '66-'67 18.5 red.
Oh and on the Crimsons, I have it on good authority that they DO NOT change color...
The Crimsons look like a duller version of an already hot old redhead IMO..