It is the later dials with depth rating between Seamaster and Professional that bubble, serial number seems to be in the known Ploprof batches and EoA has been ordered :] I really like the bezel and case as well. Here is a UV shot.
Recently acquired an original 166.077, bit of a survivor from son of original owner, sadly it seems no one serviced it for a very long time and gasket turned to sludge, thought some of you would appreciate some pictures from my watchmaker! Condition on arrival: Notice the sludge covered crown Everyt
They have several suppliers for various components and watches are completed in their HQ. Majority of watches are custom orders, so for example car at bottom of chronograph second hand is not a problem as illustrated bellow. Holes in the dial are drilled one by one if I remember.