Taillights

Yes '63 and '64 lenses are different. '63's are recessed in the center area where the '64's protrude out. And yes '64 170 lenses are different shape, but interchangeable with, 64' 270/GT lenses to accomodate the chrome trim. I would assume that the housings are different as well but have seen '64's with complete '63 tailight assemblies installed and vice versa. But I'm not very confident in my knowledge on the interchanging of lenses into another years housings as I have little first hand knowledge.