They went with the color combinations of the mud set tile bathrooms of the day....................................
That would be one opinion. Hard to tell from the less than poor quality of the posted photographs though.
Should have worded my question better, I simply couldn’t remember which engine was rated at 427 HP. Had to search and found this link below, that explains the mystery 427 was developed for Nascar and the 409 stroked to 427 CI (Z11) was developed primarily for drag racing. So that clears up which engine car in picture had, but still didn’t clarify HP difference of the engines. https://www.macsmotorcitygarage.com/inside-the-63-chevy-427-mystery-engine/