Thanks Jeff,
I've found a couple of references with some info, but they raise more questions...
U-223 was severely damaged by ramming in May 1943. She was subsequently rebuilt in St. Nazaire and returned to service in September 1943.
According to Robert Stern's book, "On 30 June 1943, he ordered that no boat was to leave on patrol that hadn't been fitted with Turm 4, including the Flakvierling" (The FlakVierling being an interim measure until the bugs were worked out of the 37mm).
According to Bernard Edwards' book, U-223 was equiped with a quad 20mm on the lower platform and a twin 20 on the upper on her first patrol in January 1943.
It seems to me that the presence of a Turm IV with a quad 20 (or single 37) was likely to have been in place when U-223 fought its last battle in March 1944. (Though I'm not sure how likely it is that she was sent out with Turm IV so early in 1943... moot point I guess since I'm interested in 1944).
Would the quad 20's get replaced by a single 37mm at the first opportunity? How big of a job would the swap be?
How did the naval FlakVierling mounts differ from the land mounts? (I found an armor kit with a 1/72 quad 20).
How would the 88mm deck gun mounting be closed over from a retrofit?
Thanks, I appreciate all the help from folks on these forums. I usually focus on researching 18th century subjects for paintings and articles and have had little time until now (retired in December) for actual modeling. A friend gave me the RoG U-Boat (he got frustrated waiting for his to be delivered by mail, and snatched up the first one to appear at the local hobby shop... of course the mail order arrived the next day)
My uncle, by marriage, was Capt. "Beaky" Armstrong, CO of the Laforey when she and U-223 fought it out to the end. I have been researching and ordering kits of his commands (Wren, Maori, Onslow, coastal forces MTBs and Laforey) and significant opponents (Bismark, FW-200C, He-111 torpedo carrier, Do-17 missile carrier, and two U-Boats, U-589 and U-223)
The RoG U-boat and all the internet traffic have made it my first priority build... which leads me to a more pragmatic quesion..
Is there an aftermarket 1/72 Turm IV conning tower available? It might be a bit of a challenge at my skill level to scratch build one...
Thanks, again
Alan