I ended up using a number of screw-hooks to hold up pulleys (each of which is rated for 220 pounds), through which I threaded 1/8" twisted steel cable. (500 pound test) In this picture you can see some of the felt I used to keep the stops from rattling while I try to sleep.

The ends of the cables attached to what their packaging calls "scissor hooks". These are nice because once closed, there's very not really any way the bed can be simply lifted off them.