[Boater Sam]

Thanks, Al.
There was maybe a suggestion in an earlier post from Lawrence that I should continue ad nauseum to find the root of the fault rather than find a solution.
However, I now don't have the time or persistence to do so, fixed is fixed.
In an ideal world I suppose there is always a better solution.
Is the addition of one resistor in any way worse than using a substitute valve of a different number for a hard to find replacement?
I used to be a pain in the butt perfectionist but advancing years and experience has taught me that nothing in this world is perfect, nobody gives a damn so why worry about the little things.
The radio would have been just so much recyclable waste anyway if I had not spent some time and cash on getting it working. It is all a fruitless effort anyway, the generations after me will not show any appreciation for my efforts.
When all the available programs have been withdrawn, these sets are going to be worthless unless we all use illegal pantry transmitters, or carve them up to fit USB ports or Bluetooth. No, they will be consigned to the bin.

The next AC41 is on the bench. Sadly it doesn't howl or motorboat. Its so insensitive that it is hard to hear any transmissions at all. It appears to have been well twiddled, something I avoid doing unless absolutely necessary.
The wiring is in much better condition however, even the bulbs work!