Configuration With Imported Models

Trying to take a family of imported parts and create a configuration. No problem with a part in a part, supress all but one but I need sketches to change from one to the next. I'm thinking if I do a block around the part, subtract and project that edge for my sketch but I don't know how suppressing/ un-supressing will work with the subtract. Anyone have other methods that work?

This is to program tool paths.

Thanks

SolidworksConfigurations design Tables