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There is a Body Tag analyzer in a different part of this website. See: https://firstgenfirebird.org/body-tag-analyzer/

Could that 053 be a bad stamped 05B? (2nd week in May)

The 2WG options show it got a 2 speed automatic which indicates it was probably a 326 if it had a V8 originally. The 400s with automatic got a 3 speed.

Depending on the amount of changes since '67, there were several other differences between the 326s and 400s; body and bumper emblems, different hoods, grill chrome, engine chrome, etc.

Various engine number stampings can better identify the engine in it now. See: https://firstgenfirebird.org/1967-i...n/1967-drivetrain-id-number-information/

And, to find out details of the original build can be obtained from Pontiac Historical Services (PHS) at http://www.phs-online.com/