Soul Limbo was the title of an album and single released in 1968 by Booker T and the MG's, who first scored with 'Green Onions' in the early 60s. Soul Limbo was a popular dance tune when I was DJ'ing, but it lost a bit of its 'underground coolness' when adopted later by the BBC, so I played it a bit less. .
The follow up hit was 'Time is Tight'.. a film theme, released in 1969, which again was standard fare in the soul clubs and 'discos' of the time.