I pulled the lot out - seemed to me to be just as much work to disconnect everything whether you take it right out or not so I preferred to have it all out of the way.
Also removed doors, bonnet, centre console and drivers seat for a bit more room to work.
I found the job simple but time consuming - just need to be methodical.
I kept every clip, screw, fastener in separate small plastic bags and kept them in strict order. Re-assembly was very easy - just used all the clips/screws in reverse order.
I also tagged all electrical connections but it was unnecessary as it was very obvious where they had to be plugged in during re-assembly.
What really slowed me down was all the aftermarket wiring for accessories I had added over the years.
Here are some progress pics...