In Canada (and it would seem the US as well), "Heavy Disguise" was picked as an a-side, with the UK a-side "Benedictus" on the flip.
"Heavy Disguise" is definitely the A-side of the Canadian release. The Canadian a-side is numbered "2326" and Benedictus is numbered "2327". The US single doesn't identify the A-side, but the 2326/2327 numbering is the same: the lower number is usually the A-side - compare the US "Man Who Called Himself Jesus (1593)/Poor Jimmy Wilson (1594).
US promo release
Not known whether this got beyond promo status.
Japanese B-side release
"Heavy Disguise" was used as the B-side of the Japanese "Part Of The Union" release.