Hi Dan
I agree there is always a danger when taking a museum subject as gospel, especially any of the U-boats as they have been subject to the ravages of time. The most obvious example is the U534 the tower has been built completely from scratch, as has most of the upper hull, look at a picture of her as she was being raised, compared to even pictures whilst in the hands of the Warship Preservation Trust.
With the best will in the world it is almost impossible to accurately repair a 60 year old boat to represent her at an earlier time, as during her life there will be various modifications and repairs, during and after service, this is true particularly of the U505 which was patched up during her layover in the Bermuda, followed by 'secret' trials, by the time she reached the Chicargo river she was even sporting a fresh (incorrect) paint job.
Those of us who are trying to research our respective boats to model will acknowledge how difficult it is to find confirmed details about a specific boat. Where modellers of the U505 wins is there are several pictures available of her during her operational years and to be fair Revell have done a pretty good job of representing her when she left on her last combat patrol. Most other boats are being modelled on poor quality pictures, anecdotal evidence and guess work.
Regards
Jon