How can I compare sketches from different models.

I have a new model very much like an older model.

I need to machine the old model to be like the new.

I will have to plug or make covers/inserts for some of the exsiting features on the old model.

I need to see the old features in comparison to the new.

Very simple thing in other cad programs.

There must be a way to do this In Solidworks.

Thank You,

Tom

SolidworksParts And Features