Finally fired her up and big disappointment. Rough as hell and I think only firing on No 4 cylinder with lots of smoke/unburnt fuel. So several hours of pulling plugs and checking HT leads, dizzy cap and rotor capacitor, hot wired to battery to isolate Ign sw, disconnecting servo and vacuum to filter etc. Looking down the carb the acc pump was discharging fuel when throttle opened and some plugs were wet so I was convinced problem was sparks. I checked each cyl in turn at TDC and respective plug sparked, but not great sparks and for one plug I could hear the spark better than see it! till I noticed it was up inside the core from insulator to sidewall rather than across the tip electrodes. These were 4 new (in 2016) Bosch W8CC RUSSIA plugs that had only had a few hours test running and whilst the problem may have been carbon deposits rather than cracked insulators I was exasperated enough to fit a set of old GM long reach plugs with similar length of insulators and bingo firing on all four. Not only that but for the first time ever I was able to get proper control of the idle using the volume screw. Then I reconnected the filter, and vacuum lines and took it down the drive and the servo works brilliantly and makes a huge difference. Finally feel I can move on to the interior.