[kramarczyk]

If you want to maintain an accurate BOM while shortening the rail, I recommend that you add the C-Base Rail to an assembly (presumably called Rail-Short or Rail - Long) and then add an extrusion(s) to cut the rail. You would then make a print of Rail-Short and flag out the use of the C-Base Rail in its construction. Save-As disconnects the new geometry from the old which may not be desirable. Also, if you add information to the AM rail at some point, like a hole or some iProperties (cost data) then none of the Save-As geometry will update, but all the stuff modified at assembly will.

Don't forget to pay attention to where the holes are in the AM rail are as you shorten it; it may be beneficial to take some material off both ends so that the hole patterns remain centered.