Thanks Tiger.
I did some further checking and found that the assembly was as far into the steering as needed. I backed off the black cap 2-3 turns and the key would then turn. However, it now sticks out past the face of the locking cylinder. When the key is turned to position 2 to start the engine it does not spring back as it used to. Just before I stopped for the day, I did a quick check on the lights and they seem to be the same as when I started i.e. it seems that the ignition switch was not the problem. Now I have to replace the old switch :-)
Thanks for the support.
Such is life :-)
MR