it starts and wil rev fine, no leaks etc etc, but, I cant get it to idle.

then remembered that we stupidly connected the distributors condenser lead to the air cut off solenoid on the carburetor - so, tested the solenoid and nothing.

So, I've just spent several hours trying to find another one and have been quoted a minimum of 4 weeks delivery time from Germany https://www.vwheritage.com/classic" rel="nofollow - https://www.vwheritage.com/classic and  https://www.volkswagen-classic-parts.de" rel="nofollow - https://www.volkswagen-classic-parts.de

Anyway, I found one eventually in the UK for same day dispatch at  http://www.carburettorspecialists.com/default.htm" rel="nofollow - http://www.carburettorspecialists.com/default.htm

Eric who runs that place is a mine of useful info, and knows his carbs!

During my search I also came across these useful sites 

http://www.volksmagic.com/" rel="nofollow - http://www.volksmagic.com/

and this Solex Carb Tuning Workshop

https://www.limebug.com/how-to-guides/view/22?article=22%25253ftitle=" rel="nofollow - https://www.limebug.com/how-to-guides/view/22?article=22%25253ftitle=