I would first say you want something like a Yo-Yo suspension system, but they are for the reflector/bulb only and max out at 24 lbs per pair. It sounds like you need to move the ballast also. Without using a pulley and about 50 lbs of counter balance + a Yo-Yo the only thing I can think of is a Suspend-All tool hanger system. They have an adjustable friction system to hold assembly line tools for workers. I think they are a bit of coin though. You could try creativity with some springs and gas supports from a hatchback...