I need to shorten it about 4-5" due to low ceilings....has anyone ever done that?

This may be more difficult than it sounds.    Cutting five inches off the drop tube is the easy part.  The problem is the support arm at the back of the machine and the hopper which has a compound curve which could be really difficult to reshape.  Everything below the curve is bolted to the machine and needs to be where it is.  You could tighten the top and bottom bends and cut a section out of the middle to line everything back up, but it may be easier to lower a section of the bench and load sitting.  Not ideal, but a simple solution.  Simple is good.  Good luck.