Thanks! This is the interview.Reading the interview, this instrumental isn't Alexander The Great (perhaps, part of it was added), 'cos Bruce says Steve already had a song about a greek warrior and I wonder which Bruce song was going to be on the record.
The interview doesn't really disprove anything about the instrumental's relation to Alexander. Yes he says there is a song about a Greek warrior, but he also says all the songs are 4-5 minutes in length. It's not a big stretch to suggest that the instrumental got shoehorned into Alex sometime after the fact. What Bruce describes definitely sounds like a lot of what is in the Alexander the Great instrumental, challenging guitar parts, weird rhythms, etc.