Thanks for the advice on the door lock, the grub screw was behind the door seal so I wouldn't have been able to find it without help.
The lock itself works fine off the car but is so stiff in place that I have bent two keys...partly because it sometimes works almost okay.
It looks as if I need to remove the interior window trim to get the runners out to create enough room to get the door latch out.
I have removed the screws from the frame but it still seems to be secured somehow. It appears that the quarter light comes out with the frame.
Is that correct and is it a brute force and ignorance technique to get it out.
Apologies for all of the questions but I am more familiar with Morris Minors.