So latest update. Ran the engin in the dark and there doesn't appear to be an wayward sparks. Set the timing with a strobe, took the carb off and blew it through with a high pressure airline and checked everything else. Engine starts and runs well from cold but as soon as it warms through it will no re-start happily. A couple of drops of petrol into the carb and it fires up. Earlier this afternoon it was running fine and fairly smoothly although still very reluctant to restart. Went back just now to have another attempt to make run it better and once it was warmed through the idle speed is very erratic slow then fast, no amount of twiddling with carb settings makes any difference. At this point the coil is to hot to touch. It's a newish coil but does this sound like it is causing some of the problems?
A quick run down of the ignition / fuel system is
New alloy tank
Red top facet fuel pump
Fuel regulator set to 6psi
Edelbrock carb ( already on the engine)
Mallory distributor ( already on the engine)
Ignition set to 6 btdc
Coil and ballast resistor both replaced during the build
Standard 3.5 V8
Any advice or help will be greatly appreciated as I just need it to work!