Thanks for all your advice everybody, have now tried everything
you all suggested!
The thing I was confused with was, the bit about the magneto base-plate rotating out of position!! I noticed that the base-plate hole on the points was not cylindrical and on turning the screw either way on the odd occasion nothing happened wouldnt open or close!
I took the points out and gave them a good clean and inspection put them back in and they did not seem right. I did have a spark!
When I turned the screw again the points would not open at all, I had to use two screwdrivers, hold the points open'20tho and then lock them with the big screw into position.
(didn't feel right though) Is the small screw the base plate screw and the larg screw the locking screw??
The engine still wont run, even put the bing carb on from my other tatty
good runner featherweight!
HELP 
PS,
The screws holding the points in place 1 small, 1 large.
The small screw isn't screwing true, its all wibbly wobbly to want for a better word, Is there any way of renewing it, only it doesn't want to fully screw out, or in for that matter!
Any ideas?