I'm thinkin' a cool motor would be an RB, longram style, but twin turbo'd, either blow-through carbs, or EFI with the turbos where the longram carbs would be... Inboard headlamps look like a good place to duct air from. Not sure what all the '61 color choices were, but that body style is wild enough that it doesn't need any graphics to stand out. Might be amusing to go with 2-toned stock colors, but that's just me.