Thanks for that Stuart, I might just go for one of them and build one good one. The shame is that the one on the car looks like new (ish) but seems to be leaking from a couple of places - the weird thing is that the car will not start if left for more than a few days. It bursts into life with some good ol' Easy Start. I have tested the output from the fuel pump (seem OK), and from the Filter King to the carb (strong), but have found that the carb just does not store petrol in the float chamber. Always got a strong niff of petrol even though checked all connections for tightness.
Ah, the beauty of running a classic ....