Hello Ewan, I was a seventies kid as well, but don't remember seeing you there...
One of my favourite Dinky toys was the big blue, white and yellow Mercedes-Benz truck and trailer, it had fabulous suspension on all axles, opening cab doors and a roof mounted air-vent that pulled up a little way to let out the smell of all those burgers truckers live on!
This really was an excellent toy, huge scope for carrying old damaged cars in the load areas and for many years, I was a trucker, driving this thing all over my Mum's table and I know I learnt some of my driving skills from this toy, that set me up for when I became a real truck driver, great stuff.
Sadly it went with all my other toys when they got stolen from a garage lock-up and I have not really been able to replace them, far too many.
Regards,
GHOSTHUNTER.