Bob,
I've only just found this thread via yesterday's posting from Margaret Kennedy, so I don;t know what progress had been made.
I like Paul Clayton's work, probably for the very reasons you mention that he fell out of favour!
I don't know if you have received this or not but I have his LP 'Whaling Songs & Ballads' on Stinson, with his liner notes. If you would like a copy, please let me know via the Mudcat and I will e-mail them to you
Good luck with the project
Jan