6 channel sound

this is kinda a tough one. Recently, I acquired a copy of the movie History of the world part 1, and I thought the sound was bad, so I thought I'll extract it, clean it up with Audacity and stick it back in the movie. I currently have the 6 audio tracks from the movie....but I have no idea how to stitch them back together as a 6 channel whole and re-insert them back into the movie. I do have iMovie and mkv tools if that helps....

thanks for any advice on this one.....

John Brine