Hi Gert,
Thanks for keeping this discussion on edge and sharp
.
I will explain my findings a bit more. Stutzpunkt IV holds both the Marine Flak Batterie Nordmole as the Panzermauer with the two 625b's (occupied by the 723 Grenadiers). See the map below (with the letters H(eer).M)(arine).). So this Stutzpunkt was both manned by the Marine Flak Abteilung 813 and Grenadiers Regiment 723 (It was not unusual to have infantry to protect a Marine Flak Batterie, especially in a Panzermauer with 625 bunkers).
I have also mentioned the old town (Seinpad) before as a possible residence for your father. I thought it was less likely though because these houses were mainly occupied by officers, at least around the time you're father was there (around that period this Old Town was destroyed, except for the Seinpad). But It is a real possibility. These houses are also very close to the 625b's as mentioned.
With all due respect to the Atlantikwall Museum, their archive with German documents is limited. If they really mentioned Wn. 17 as the spot for a Pak 40 I am really curious which source they used. But as they are also referring to a 625b, I think they mean the 625b (1405) that was the first bunker that housed the Atlantikwall Museum. But it is part of Stutzpunkt IV. Wn. 17 houses their current museum (in the 611). To further explain my findings, see the images below.
About the private message. You should be able to click on 'private messages' on the top of this forum..? In General: I was thanking you for this great opportunity/discussion and I am offering a tour through Hoek van Holland, if you are ever (want to be) in the neighbourhood.
O, and the map placed by alex, you will also see a 625 in Wn. 18, but this 625 housed a 4,7 Tsjech gun through the entire war.
To conclude (at least in my personal opinion). You're father should have been stationed in one of the 625's (1405 or 1406) in the Panzermauer of Stutzpunkt IV. See my previous posts of pictures of these bunkers (and the soldiers that occupied number 1406 around march/april 1944)
I hope these maps will make everything clear.
* extra note: on one of the maps the 7,5 fieldgun in the 611 is suddenly gone. This is probably because of the gun change and modification of the scharte of the 611 for the 5 cm K.w.K.