Ignition Query

[Tom2000]

Whilst the car was at a Triumph specialist over Xmas they stripped the carbs and completed a waxstat conversion amongst a few other bits. They mentioned it would be a good idea to install either a new ignition barrel or switch? (not entirely sure if i've remembered this correctly) as it is worn and is making starting/cutting the engine abit more of a mission than it should be. (Suspect cause of light over run).

I have a 1500 spit, do I need the harness & the column lock? or would it be a good idea just to do both?

Thanks

[bodders1]

If the key needs wiggling around in order to make it turn, that indicates a worn/damaged barrel.
If the key turns readily, but the ignition light doesn't always come on at the second position, or the starter doesn't start cranking at the 3rd position, that indicates the need for a new switch.

It is unlikely that the switch is causing your running-on.  Assuming that by "running-on" you mean the engine carrying on firing on one or two cylinders for a few seconds after turning off the ignition, this is not caused by a faulty switch.  It is caused by localised hot-spots in the cylinder head being hot enough to ignite the compressed fuel/air mixture without the aid of a spark plug.  It is unusual for this to happen in all 4 cylinders at the same time, so the running-on is characterised by a lumpy, hesitant engine sound.
Running-on can be an indication of a weak mixture, or of excessive carbon build-up in the combustion chamber.

hope this helps
bodders