Came across this old thread and thought I'd add more info on my GPW as I'm still trying to find out its history.
Like Ian McCallum's mine has
Brass choke/throttle cable heads
rounded/square clutch /brake pedals,
these I always wondered if they were correct as I'd never seen a square one
Unfortunately the body had been stripped down to bare metal in the 1970's so no marking are left
data plate