I was working on this film at Pinewood Studios in 1972/3 during post production. This film had two stereo mixes. Both were 4-track stereo format (LCRS). Gordon K. McCallum, Theater Two's resident mixer (where all Pinewood's stereo mixes were created) was on vacation. Keith Grant, a well-known British popular music mixer stood in for him. When McCallum returned he reviewed the mix done on his stage and was dissatisfied. He completely re-mixed the film. Presumably both mixes were returned to Universal. The home video version is a two-track mix-down of which mix I have no idea. I contacted Universal about this and, up to several months ago, they could not trace any 4-track stereo material in their inventory. Hopefully if they are found, they will both be properly identified and that the McCallum mix, which I recall preferring, will be presented sometime in the future in its proper discrete format.