Just curious, but what is it about those two photos of a couple of beautiful 67 Vette coupes that makes you think they have the L88 option?
On the 68 Vettes, I believe the handful of L88's that were produced had a larger (taller) cowl induction hood to accomodate the high rise intake manifold. I don't see any outward cosmetic changes to these two Vettes that would tip anybody off as to what 427 engine option they may have had. Except the black one seems to be missing its 427 emblems on the scoop.
I'm certainly no Corvette historian, so if I'm missing something here, please enlighten me.