These units are designed to be used on C-stands. They're much too heavy to be hung from the track light. Hung from the ceiling the switches will be inaccessible and the clamp looks flimsy at best. Lights are usually hung from a pipe with a c-clamp.
I'd keep them on the floor, on C-stands, with a sand bag on the base of each stand to keep it from tipping, which soft boxes have a tendency to do. This will give you maximum control of the amount of light and maximum flex for positioning the lights as well.
If you do decide to hang these instruments be sure to use a safety chain on each to guard against the possibility of a nasty fall. And be sure to us gaffer's tape to tape down the cables for each light.
