2 Ways you can do this........... either buy a kit or buy a relay, wires and a button to start the engine
I choose the richbrook one, if you buy them seperate make sure you buy the right relay, the diagrams below will help you determine which one you need and can be bought from maplins i think
1) First of all disconnect the battery before starting and remove the surrounds round the steering coloumn by undoing the two torx screws
2) Mount your push button start were you want it, i choose the gear stick surround, the richbrook one had to be 19mm but i never had a drill bit that big do i drilled a hole with the biggest bit i had then used a dremel to sand away the plastic to fit the button, use the bezel you get in the kit as a template
3) Now its time to start wiring up, from the button there are 2 terminals one is for earth and one is to go to the relay, i used the earth were the electric windows are earthed but feel free to use any earth
4) Now wire up the relay like so :-
5) The ignition and starter wire are wired up like so, the blue wire is the starter and has 100 printed on it and the ignition is the brown wire which has CC01 printed on it, but use multimeter too just in case
Install an inline fuse on the wire going to the ignition with a 10 amp fuse and put it somewere that its easy to get to
6) You should now have it all wired up like so :-
7) Tape any bare wires up, attach the relay somewere it wont get knocked and screw in place
8) Replace the steering wheel surrounds and connect the battery back up and test
Hope this helps people for a cool gadget
*Also if your wanting both key and button to start the engine dont cut the blue wire just splice into it like the ignition wire
Just PM me if you wante me to make you up a kit of what you need, will work out cheaper than the kits, less hassle with a kit though all ready to go