Where ever you want. Make them fit and look like they came from the factory that way.

Relocated the fog light switch in my Bonne. Used a GP one wouldn't ya know


Or toss an IC, EWP and ABS defeat button/switch in


Add your own homelink or extra switch where the factory put a fog light switch.


Add heated seat buttons...


All the above was added and not factory. SEM sells paints and texture that replicate the factory stuff. You can do it and make it look factory if you'd like.