Here is what I know about this valve:
FoMoCo box has C3DZ-6A666-C part number.
Part has Ford engineering number C4UE-6A666-A.
Plating is pretty much as you see in the photos.
It is definitely an AC valve and has what appears to be an original AC paper part number tag.
I would like to trade it for a pair of NOS fastback quarter interior lights. I did a test fit of the part on my 65 motor and it was a correct fit for the elbow style PCV hose and the grommet in the valve cover. Send PM if you are interested in a swap.
[Blocked Image: http://img230.imageshack.us/img230/2981/03lk4.jpg]
[Blocked Image: http://img230.imageshack.us/img230/5177/01tl2.jpg]
[Blocked Image: http://img230.imageshack.us/img230/4735/04xj5.jpg]
[Blocked Image: http://img227.imageshack.us/img227/796/02eu0.jpg]