Here's mine:
Volvo B57; Volvo B55 Ailsa; Leyland Victory; Leyland Victory
(air-conditioned); Albion Viking; Leyland Viking VK44 (9m, 12m
versions) Mercedes O.303; Mercedes O.305 double deck; Leyland
Atlantean (PDR 1A/1; AN6
; Hino RK.
Oh, and also, Mercedes-Benz don't make any 3 axle bus chassii, so
the chances of a Merc superbus are slim.