Hi,
There are 2 types of dial for luminor marina models (with a running second at 9 o'clock). One has the sausage dial (PAM001A,B, PAM111E, F) and the other has a sandwiched dial (PAM111H).
Sausage dial has 2 types of caseback. Closed and see-thru type. A and B series for the closed caseback and E and F series for the see-thru caseback. For the see thru caseback, it is easily recognise as the word "Panerai" is engraved multiple times on the bridge on the movt.
Sandwiched dial on has see-thru type caseback but usually start from H series onwards. The bridge has a more simple and cleaner look.
Both are handwind movt watch.
For better accuracy, I will prefer sausage dial model with closed caseback. (Angus is selling the ultimate PAM111E series. you may like to check it out)
Hope this help