Study "Assembly.skp" before proceeding (it can be viewed with the free version of Sketchup 8).
Carefully remove the base from the solar powered devil (or hula girl, snowman, etc.). Once removed, I placed a dot of cyanoacrylate glue on each end of the solar panel to hold it in place.
Print "Base.stl", and fit it over the solar powered base, such that the solar panel tower protrudes through the rectangle in "Base.stl".
Print "Solar Cover.stl". Slide "Riser.stl" into slot in "Solar Cover.stl".
Slide the "Solar Cover.stl" and "Riser.stl" assembly over the solar panel tower.
Press the magnet between the fins of "Whale.stl", just enough to hold it in place.
Run thread from "Riser.stl", through the eyelet on top of "Whale.stl", then back to "Riser.stl". Adjust the length of the thread such that the magnet is 1 to 2mm above the top surface of "Base.stl" and nothing drags.
Turn on the lights and watch it swing.