no affect as (a) 9x6s have pretty rudimentary electrical systems and (b)European models are set up this way (a little different wiring set-up but essentially the same). All you are doing is altering the ground.
That said, on 9x7 models, there is a set up feature in the PIWIS software which can be changed to make them flash (as European models are set to). In which case, doing this mod on them might/probably would create an issue the computer would pick up.
Use due caution when removing the plug retainer clip (it's yellow) and the bracket as they can sometimes be brittle and you don't want to crack them. Otherwise, you may need to replace in order to get the headlight pod/wiring plug to re-seat properly.
Good luck
