Well, Stanley, I'm glad to announce I now have the soundtrack.

I'm a total newb to multichannel audio, but I went and did it anyway: I took the italian Gout soundtrack, which (if the software didn't lie to me) was Dolby Sorround encoded, and upmixed it to 5.1 using TFM Audio Tool. I then married the result to Hairy Hen's LFE channel from his 70 mm mix, and the result is a strange hybrid that I'm going to test drive tomorrow morning and drive the neighbours mad!
If anyone wants to hear a sample, just ask and I'll upload one.