Kid's book from 60s / 70s - something conspiracy ?

[Frenchoid]

I read a book at school in 1977, ad I'm pretty sure it had 'conspiracy' in the title. Possibly The something street conspiracy?

Plot involved two gangs of kids in postwar Britain - they'd have carefully staged 'battles' among the bomb sites, involving go-karts customised to make 'tanks'. One of the gang leaders was called Topper. In the story, the rival gangs join forces once they accidentally rumble a contraband racket involving a fearsome builders yard owner. The climax of the book is an elaborate plot cooked up by the lads to decoy and capture the miscreant and his sidekick, while avoiding the guard dog in the yard - involves luring the sidekick up into the church tower.

Amazing that the plot's stayed in my mind while millions of useful facts have long since jumed ship. So - any ideas of the title, anyone? Thanks!

[ergonzo]

i believe it is called the Otterbury Incident. I can't remember who wrote it but it might have been somebody with the surname Lewis. my copy had illustrations by Edward Ardizzone if that helps to track it down.

[ergonzo]

And I think the author was Cecil Day Lewis

[Frenchoid]

Bang on, ergonzo - that's the one !!

Don't know where I got 'Conspiracy' from - I think I must have been mixing it up with the Cato Street Conspiracy from my history lessons of the same time...

Anyway, many many thanks !