I'm getting further into the book now; the B-17 was the first aircraft to be located, purely thanks to it's size (they were using a radar device to look through the ice) They had a good idea of where they were, but the precise location was difficult to ascertain as they had several hundred feet of ice above them!
It was always the group's intention to bring back a single P-38; it was reckoned that was the best bet for attracting investors. However, the amount spent far exceeds the value of one of these; most investors wrote off what they spent. Once I get to the end of the book I'll do a little maths. I'm not knocking the guys who pulled this one off - it's a fascinating story, and they deserve a great deal of praise for their achievement.