I fitted a nice little memory device bought on eBay for £28.99. See item 322352078637 by seller idegencris.
You connect it to the back of the switch. It is only three wires and he even confirmed the method for removal of the switch and the wiring. Which ever position you decide to leave it in, it will remember that for the next start so you can have it as normal stop/starting or if you turn it off it will do that 4 seconds after the next time you turn the ignition on.
The radio trim needs to be removed in order to push stop/start switch out. The switch comes out easily but the radio trim was tight but I can advise where the catches/lugs are so you know where to pull it. I then pulled to harness out through the opening left at the side of the radio to work on it. I backed the three wires out of the plug as that way I could finish it off with heat shrink and then push the pins back in. I do tried to add a picture of it and the picture the seller gave me explaining the switch removal. He also told me the wires are connected as such (I did confirm and luckily they are all on one side of the connector).
(Module -- Car)
BLUE -- Brown/Black (signal)
RED -- Black (acc/ignition)
BROWN -- Brown (Gnd)