[Held for Ransom]

Yup, I screwed up.
First picture was labeled correctly as a '75 400 (WT) piston.
Second picture was a '67 400 (YC) piston.
Third picture was a '72 GTO 400 piston.

Now, the new 2 pictures are of the '78 YA and X7 pistons.
The flat top piston is from a '74 GTO (350).