Hello, My version of fsfs-reshard script is able to unpack revisions and revision properties of a FSFS repository format 4 (Subversion 1.6) Probably there is not a lot of job to do to get it work with Subversion 1.8 format 6. I have already planned to work on it this month.
https://github.com/ymartin59/svn-fsfs-reshard Regards -- Yves Martin