The red background on the 1968 Canadian 427 cars was a real thing. They didn't really make or sell a lot of L36 cars (the only version of the 427 dropped into Canadian '68s). The different colour on the emblem was mirrored on the Canadian Pontiacs with the L36: instead of red paint fill as on the 327 / 396 cars, the paint fill was sort of an ochre yellow-orange colour.

Link to Cdn. 68 Pontiac emblems

It is kind of a trivial thing but yes, the SS427 wasn't badged as an Impala in 67 or 68, even though we knew they were Impalas. I do remember seeing a 1968 preview article which showed an early (pre-production?) SS427 convertible that in addition to the correct badging, also ran with the Impala Super Sport grille emblem like a typical Z03 non-Z24.