So I rewound, listened to the last 20 seconds of the track again, and this time recognised what my brain was expecting - the opening chords of Number Of The Beast. Clearly, back in 1988(or so) I made a mixtape that followed up W.A.S.P. with Iron Maiden.*
Aaaah, them were the days.
*I wonder if I could use a similar process to put back together the entire album. Sadly, I suspect that many of the linkages would by now have been entirely overwritten.