Figured I'd use this build thread to keep it all together.
As you peeps were aware, the air suspension on the OSF corner had gone caput. After much deliberation, I decided to bin the air suspension off completely and go the coilover route. As far as I'm aware no one else has done this (here in the UK anyway) and I always like to be different.
Before I move onto the coilovers, I decided to sort out the OSR balljoint as I've been meaning to do this job for months.
Firstly remove the airhose from the top of the airbag:
 
Once the airbag has been deflated, you get a proper dropped look... O0:
 
The nut at the bottom and the bolt at the top need to be removed:
 
This is the bolt from the other side:
 
Once the bolts, etc are removed the lower arm drops down to access the balljoint:
 
The BMW tool is placed over the end of the balljoint:
 
From the otherside:
 
Once removed (makes easy work of removal of the balljoint):
 
 
You use the tool from the otherside to pull the balljoint back into place and then bolt everything back together.