Another - while not a Z-11 perhaps the best example of what the plants turned out as far as detail evidence.

FWIW the above photo is of a 350 300 engine assembled in Tonawanda - engines assembled in Tonawanda in 1969 were painted with the exhaust manifolds - Flint engines were not.
So if there is a T on your assembly stamp the manifolds and the locks etc should have traces of paint.

In the wiper cowl well area like William stated should be Orange... because when you look through the wiper grille the color remains consistent, same reason Z28's had the wiper well painted stripe color.

Isn't this NovaJoe's engine compartment?

Something neat about the Tonawanda sticker on the pass side valve cover, it has a clear overlay and is on the engine prior to painting, after which the overlay is peeled off and reveals the foil sticker, it leaves a little rough edge of paint...