Making a Curved Cut Based on a Surface

Hello All,

I'm sure this kind of thing has been answered before but I'm fairly new to these forums and could use some help.  I have a fixture that I am designing for our production line.  The goal of the fixture is to mount our product up verticaly from the face.  I have designed it so that it will do this, but the right now, the product, which has a curved face, sits on a flat surface.  I want to be able to make a cut in the fixture to perfectly accommodate this curved face but I'm not sure how.  Any help would be greatly appreciated.  I have attached a screenshot of the assembly to illustrate what I am working on.  Thanks very much.

SolidworksSurfacing