i have an assemly that i want to analyze using shell method. how can i extract midsurfaces of components of this assemly? if i save it as a part, it will be a set of overlaping surface bodies in the areas where two assembly componets are coincident. so i need to do alot of trimming and knitiing. after that it turned solid, i need to extract midsurfaces one by one. whats the correct way to do it faster? any ways to do this type of work inside the assembly instead of saving it as part?

i'm using solidworks 2010.

thanks in advance.