Area Hatch

Hello,

I am trying to make a drawing where I have a piece of equipment located on a large, formed surface.  I need to make a drawing where the piece of equipment is shown with hidden lines removed, while the surface is shown as hatched.  If I try to hatch the surface, it hatches the WHOLE surface, which means that the equipment is hatched also.  Is there a way to just add hatching to the part of the surface that is visible.  I know I can cheat with sketches and boundaries, but this is a very complex part and would take a long time to do this way.

SolidworksDrawings And Detailing