[Lynn]

Post on top is correct.

I think these are being reproduced now; but not certain. If it is, you can bet there is something wrong. Not sure why no one can reproduce parts exactly the way they were.
They were not for many years.

I have an NOS round post top stamped with HS 248. Part number on the box was 25036504. I don't think it is assy line correct, as the assy line parts were stamped AC before the digits. The BOX says ACDelco, but no AC stamped on the part.

I also have an assy line sender with NO tool marks on it. Tested and it works. Stamped AC 257M. Not sure if that means it doesn't trigger until the temp hits 257F.

The assembly line sender one has the correct connector on top. They are really hard to find, and I hate to separate the two parts.

First three pics are the assembly line part. Fourth is the nos part.