Hi.  I imported a Step file of a car, which is one big surface in the feature tree (says "Surface-Imported1").  I need to thicken it so I can use it for a flow simulation, but it pretty much won't let me do anything with it.  There are gaps between the individual surfaces, but since it was imported that way, and shows up as only 1 thing, I can't knit it or anything.  What is weird is I can click on the surface and highlight an individual surface, but I can't do anything with it like copy it or move it. 

Attached is a photo of the problem.  Notice that the imported surface is only half of the car, and it let me mirror copy it, and then scale it to proper size.  Also notice that I can click on one "piece" of the surface (in blue), but that piece is highlited on the left as the imported surface- so I can't edit or copy just the blue part.  What I was hoping to do was to click on each "piece" of the surface, duplicate it, move it over a few feet, hide the original imported surface, knit the copied pieces, thicken, and then use that for my flow simulation.  Any help would be very appreciated!  Thanks.