So I believe I have found at least the port and starboard light groups mentioned on Kabelbild der licht, but I wonder if I am mistaken. The Kabelbild shows what looks like 3 lights on the port side and two on stbd, but if my photo is correct, it is the opposite.
U-575INTPlate8-C.jpgWhat I believe to be true on U-995:
Bb side, overhead, between D.Spt 72-73 and between 73-74.
Stbd Side, overhead, between D.Spt 72-73 (see photo) 70-71 and 67-68.
Below is a close up zoomed-in shot from the
http://www.kubische-panoramen.de/index.php?id_id=5380 image. If you look at the Stbd side, you see what looks like the location of a light socket that mirrors the remaining one on the Bb side. Am I wrong?
Surprisingly (to me) it seems that there would not be a whole lot of light thrown on the torpedo tube area - where one would think it would be prudent to have some light...
(this edit added an hour later) Or... perhaps the socket is visible in the top left of this picture
engranajescabrestante.jpg from u-historia. It would put light between the tubes and where I thought there was a socket on the Stbd side of 74 was my imagination.