I don't see why it'd be necessary to mount it. It's not like it's going anywhere with something on it. Probably dang heavy enough on its own that it won't move empty.
It's pretty darned wobbly right now, Rusty, when the ramps are lifted all the way up, even with no vehicle on the lift. But that's because it is way out of level, so I haven't adjusted the cable tension yet. I'm going to level it up by using pieces of plywood of different thicknesses under the columns, then measure the plywood and buy steel fish plate of the right thickness. If the lift is still unstable after doing that, then I'll have the plate drilled and attach the lift to the floor. I'm hoping to be able to put my B200 van on top and my '62 Valiant under it during the winter.