Punch a Tab in a Curved Face

Hi All,

I've been working on this for a while and haven't come up with a solution.  The part in the image was imported from a step file.  I don't believe it was originally created in SolidWorks.

The closest I've been able to get was by creating the curved part, then flattening it and placing the lances.  After that it wouldn't fold.  I'm open to any suggestions on how to proceed.

Thanks,

Larry

SolidworksMysolidworks