Just spotted this info. Bought the factory service manual 5years ago for my 3rd gen (UK), and got a pile of ammendments with it. Never really bothered looking through them before, but glanced through them tonight, for something else. With the comments above about Mazda having must have made a mistake with their recomendations for spark plugs, seems they did!
2 of the extra pages that came with the manual, are from a Mazda technical bulletin (FD/036), which states that the recomended plugs in the UK car should be:
BUR8EQP - Leading,
BUR9EQP - Trailing.
This info is repeated on pages G3 and TD5.
So it seems they finally caught on that there was a mistake in the UK manual, but it took them until 1998 to issue the technical correction! Better late than never, I suppose!