Alleged comedy features Guy Arab IV/Massey 373WPU, formerly
with Moores of Kelvedon (but in Eastern National livery), and now preserved at Castle Point Museum, Essex. (thanks Paul Harrison) It's also allegedly a remake of the Will Hay film Ask a Policeman (1939) and to be fair it has a chase that copies the climactic chase around Brooklands racetrack.
Cannon and Ball requisition a bus from their local 'National' bus depot. Seen on the forecourt are two buses, 373WPU and former Hants and Dorset TD895 (HLJ44), a 1949 lowbridge Bristol K6A/Eastern Coachworks. Both have Bournemouth as their destination, but it's 373WPU they take.
As the chase begins a Leyland-National is glimpsed in traffic:
As in 'Ask a Policeman' the bus is caught in traffic and a group of passengers board -
and promptly get thrown about in the bus as it moves away:
The chase moves to a racetrack, as in the original:
.....and culminates in a head-on crash, after which the villains are arrested: