Try using a small punch so you have an indentation and then you may be able to use a small bit to get a 'starter' hole so larger size drills have somthing to bite into. Don't need much depth. You can then step up in stages until you have the size hole you need. Have to be careful as the small drill bits are easy to break when the metal is hard. The risk doing this is that the small bits break of flush and complicate the problem.

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas