Finally fitted my blue converted dials, bit fiddly but straightforward.
The green cable does indeed just pull out, no clips or catches.
The middle cable is a bit harder, you need to rotate the dial around to the right so as to remove tension on the cable then pop off the black ring at the end of the cable from it's pin.
There is a tensioner block which pushes into the back of the dial unit which needs levering off, just pry with a blade screwdriver and it pops out.
The tricky bit is that the unit is quite snug in the dash recess and needs manoeuvring out of position, there is a small black lug that sits in a lip under the unit, I put a screwdriver between the dial unit and the lip and with a bit of levering they moved apart.
You then have to twist and turn the unit so as to move it back so you have enough room to wiggle the unit out of the dash.
Be aware that there are two small metal clips that sit over the screw mounting points, you need these as they're what the screws grip into, without them the screws won't bite and everything will be a bit wobbly.
You now have access to two cable connectors, one at the top for dial illumination and the large block underneath for the fan speed control which unclips quite easily.
Unfortunately I omitted to take photos while doing the job but it becomes obvious as you get into it.
BTW, also changed the rear demister button at the same time.
One thing that's a bit of a pain is that the aircon and recirculation active lights don't seem to work, annoying but maybe I need to have another look at the pins in the connector at some point, too much time has passed to complain to the seller on eBay, ah well.