Bypass the fuel pump!
 

Just take a piece of hose and connect one end to the fuel tap on the tank, the other one on the fuel inlet on the carb. This must cause fuel to get into the carb, provided you have sufficient level in the tank.
Advice: do not check / change all at the same time.

Reading the posts, summary:
1. You have a spark - malfunction of ignition unlikely - problem somewhere else
2. No fuel in carb - highly likely this is your problem

Auke

It F**king Goes!!!!!
 

Thanks so much guys, after bypassing the fuel pump and giving the battery another charge it fired, the intractable thing actually runs now! I'm so pleased, and only a little worried that the Micron exhaust on it is too loud. There'll be time to worry about that in the morning. The clutch seemed to instantly free off as well so I think that's ok too.

A spanner check then an MOT and I'll be away. Thanks again all who posted.