Mirrored Items in Assemblies

I have a part that was initially intended to be a mirroredpart. Therefore, I created a mirrored part and have been workingwith the original part (and the mirrored part) in my assembly.

Along the way in the design process, I now have a need to havediffering hole patterns in the two parts.

Is it possible to modify the original part and NOT have the mirrorupdate? Likewise, is it possible to modify the mirroredpart?SolidworksAssemblies