Job done. Mostly easy if you have the right tools, patience, and don't mind hands that look like they've been mauled by a cat. Took me about 6 hours all up doing it slowly and carefully, with breaks and photo taking. All CPS's were original as verified by the date codes on the parts. No fault codes produced in my ownership for them being bad, so It's a bit of preventative maintenance. There are theories that these do slowly fail before producing a fault code. I guess I'll see in the next while if it's made an improvement.
Below are a few notes and pics that should be helpful to those tackling this job.
Remove the weather strip and cowling cover that runs along the centre of the lower windshield cover (4 screws that twist and pull out) gives your arms and hands a bit more working room :
Remove these 3 hoses running to the heater. About 1 litre of coolant drips out, makes life A LOT easier if you have big mits for hands :
Passenger side Intake CPS removed. These are the tools I used to remove it. There is a bracket that attaches the wiring loom box and fuel line bracket to the rear of the cylinder head. It also obstructs the hex screw required to remove the intake CPS - All needs to be removed blind. There is a 10mm bolt right in between the bracket that affixes a cover to the cylinder head - DO NOT remove it, coolant comes out. Very easy to get confused, so getting a good feel for things, and using an inspection mirror goes a long way.
In these pics, you can see the hex screw for the passenger side Exhaust cps. This is why life becomes better with those heater hoses removed and tucked in out of the way. Remove the hex screw, and pull the sensor out with the plug connected - Much easier to unplug this way.
Over to the drivers side now. The intake CPS is just as much of a c#nt to remove as you have another stupid bracket like on the passenger side in the way. I spent a good hour after trying to get the bracket back in after the cps was swapped out, but gave up. Next time I have access to a hoist I might install back in then. No issues afaik with it not being there for now. Looking at the reflection in the inspection mirror below, you can see the hole for where the car's original intake CPS lived.
Tools used to get both intake and exhaust CPS's out, and new ones back in.