It IS difficult. The bass player that I used, Steve Wolf, had been the go-to bassist in the Danny Gatton Band years ago and really knows his stuff- all the session musicians were much better than me. I wrote the horn parts for the tune and did some of the solos, but the longest solo is on a soprano sax (not me, I am not a reed player) If you PM me your surface mail address, I'll send you a CD with OMH on it. Like you say, it is not an easy tune to play. I hope we did a good job.
Years ago, Robben Ford, who is a big fan of Butterfield and Bloomfield, did a cover CD of BBB tunes. I do not think they tackled OMH, but I may be wrong.