Thanks Dave, I took your advice and just threw everything on layer 0. Originally I did not want to do that because I thought... layer 1 was at elev 1 and layer 2000 represented elevation 2000 feet. But I noticed each "topo" line was not one number bigger or smaller to the ones next to it. So all elevation layer data from USGS had no value in their layer naming convention. So I am now making surfaces of each step and extrude all of them (all 2000!) one by one and see what I get? Then I can compare it to a really hodge podge set of separate area surface tiles I am hand stitching together, and plan to slice up the mix at the same 1 foot elevation intervals and compare the two. Unfortunately since I truly don't know what I am doing the accuracy will not be determinable, but we will see if it is good enough once we get there.
Thanks again for all your help, your advice is always "right on!
Matte