If I ever get my hands on one I'll have the shell off of it pretty quick. Or at least enough to see up into the bottom.
I'm positive it has an aluminum skeleton and most of the inside is plastic.
We stood and visually compared the 160th to what we know about the 66s and normal sewing machines. The monstrosity has about half the work room under the arch as the oldies. Way not enough for me to use.
Joe