Mono only, from Dixon's tapes. The sessions were self-financed and he licensed (or as he put it, "leased") the tapes to Savoy. Sadly this record has never seen an authorized reissue since. The story is in Dixonia; I'll dig it out and transcribe later if anyone is interested.
Most of Bill's early sessions on tape were lost in the late '60s because of a storage locker mishap (I believe while Bill was in Wisconsin). A few reference copies exist and I've been lucky to hear some of those early bands with Tchicai, Giuseppi Logan, Rashied Ali et al. Hopefully some of it sees the proper light of day. There is still quite an archive up in Bennington.
IIRC the dates Bill produced in the late '60s for Savoy - Marzette Watts, Bob (Cleve) Pozar, Marc Levin, Ed Curran - are stereo, though not particularly well-recorded.