Curing the thirst of the V8 in the Rover P5b

The tick over or idle of the Rover had been lumpy for some time and setting the carbs didn't seem to help. I went through the ignition replacing and repairing but no real difference.
The fuel consumption was pretty horrendous and the car would tick over albeit it a bit more lumpy even when cold without choke.
I pulled out the starter valves.these act as a choke on HIF6 carbs letting through a rich mixture. One was pretty worn but on one carb the O ring had broken up completely. I replaced both and although I still have to reset the carbs the V8 now idles slowly without trying to cut out or foul its plugs.