Retro-fitting power folding mirrors in the early model S-Type is another easy retro-fit.

Swap the mirrors, fit the switch in the driver's door pocket. That was all there is to it.

Surprisingly, no requirement to replace the door control module or do any programming.

Now Denis wants me to work out a way to open and close the mirrors when the car is locked / unlocked. Never satisfied, that bloke

Nice one. It's the wiring already there?  Cheers. 

Except for the little bit which goes to the switch in the driver's door pocket.

Well done that man.....always at it. 😀