Ross McNeil on RAFCommands has answered both mysteries...
http://www.rafcommands.com/forum/sho...5178#post35178
B-17 abd correct date was
16/09/43
407th BS/92nd BG
B-17F-80-BO
#42-29965
Diving reference is:
"He has picked up on the reference to a number of fuselages dumped around Burgh Island (not the crash location) of Catalina Lend Lease aircraft stripped/scrapped and sea dumped before being carried by the tides to the location.
I've dived this location so can personally verify the contents."