Mark,
The old annuals had one-piece platform chassis that were attached to the bodies with screws. The screws were uniquely designed . . . unlike typical hardware store screws. They had bullet-like tips and the "threads" were spiral-like rather than typical helical screws. Unique. Designed to be easier to thread into the plastic bosses in the body, and the bullet tips pulled the chassis, bumper mounting tabs, and the radiator-wall mounted body bosses into alignment before the threads cut into the bosses.
This new Cutlass kit has entirely differently designed screws that serve the same purpose; they are more conventional appearing.
I found one of the old AMT chassis screws in a '60 Mercury I picked up from an estate sale. I gotta get to that Merc!
I think everybody (AMT, SMP, MPC, JoHan) used them. Later on, JoHan converted to plastic taper-shaped pins, and eventually everybody abandoned them altogether in favor of flat panels for gluing.
??