Apparently a lot of people had some questionable taste in color combintations back in the late 60's. There are some pretty strange combinations out there.
Maybe it was that pro drug era that made this happen....?
Or maybe he wanted a 'red/green' *Christmas car...
to contrast with the 'Halloween cars' that some of us have (in orange/black ext and interior)...
PS. Back in the fifties, yellow cars with green or blue interiors were common (in std configuration). I've seen early 90's ZR1's in RED with BLUE interiors.. and of course the most popular '96 Grand Sport Corvettes were blue with white stripes AND RED interiors! .. so unusual color combos have been optioned for by customers over the years, and mfgs have even opted for some as 'standard configurations'...