A local mini owner has said my timing may not be that far off, certainly not 180' as when we tried switching 4 for 1 and 3 for 2 it didnt like that one little bit!
Plans for him to look at it again today were called off, so I had another go myself. I turned the dizzy to 11 o clock and started turning it clockwise and eventually got to about 1 o clock where it seemed the most 'poppy'.
I took a video using my phone of my last attempt as you can hear the battery is going flat again.
s6zR3CrK01U
It pops quite a lot but thats it, even with a bit of throttle. I had better mention that the HIF38 is currently on there as the HIF44 I got is still in bits at the moment. I've checked there is fuel getting through by taking the pipe off the carb and cranking on the key, and also that fuel is getting into the head as the plugs are wet with petrol and also you can smell it coming through the plug hole. I tried earthing a plug to the head and found that the spark has gone white again now rather than the yellow coloured spark I had a few days ago. Obviously the battery needed the charge!
The dizzy is slanting slightly to the right as can be seen in this piuc.

Can anyone suggest anything else to try, or that I can check, or that I haven't done?