[William]

If the OE VIN-stamped MN or MO engine is gone and there is no factory paperwork there isn't anything left to rule it in as a COPO. Most of the required and standard COPO equipment was also present on an L78 Camaro SS. Here is some stuff to look for:

VIN: should be an 8 cylinder [124379] Norwood build no earlier than about N578xxx. Even that is a stretch; virtually all earlier COPOs were Yenkos.

Chassis: Should have power front discs [racers took 'em out], COPO-specific 12 bolt posi BE code axle. Lots of COPOs ended up with a 9-inch or a DANA 60. I have had 2 BE axles and known of several more. They aren't that tough to "create" so that is no longer an absolute indicator. All had dual exhausts and should have the hanger plate tack-welded to the LH rear frame rail.

Body: All had the ducted hood with factory wiring and holes. Optional on SS after 1/1/69. 4-speed must have Muncie-specific speedo cable routing.

Cooling: HD radiator with 90º upper hose connection. BB specific heater.

Body tag: Most are X44, some X11. A very few early Yenkos were X66 or X22. Cannot be X33, X55, X77. Some COPOs were ordered in groups and had consecutive 'NOR' numbers on the tag. Some of the groupings are known. But that does not apply to all of them by any means [not even the 50 Gibb ZL-1s] so if is not part of a group it doesn't rule it out.

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