chevy didn't put a V6 into anything until the '78 malibu.
late 1966 is when the SS option came out with a 350 small block or 396 big block. the Z/28 was also made available in december '66 with the 302.
'67 camaros had vent windows and no side marker lamps
'68 camaros no vent windows and has side marker lamps.
'69 camaros have their own body that is roughly 4" wider