I had problems with the Spyball on my bike last year. I just traced its main feed wire (it's soldered into the main ignition feed - somewhere beneath the insulation tape around the headstock of the bike), and disconnected it. The wire then feeding the ignition was just reconnected to its original live feed. It was shockingly easy to do, and took me all of five minutes!
Nothing else needed removing. The alarm/siren etc. is still in place on the bike. I've had no problems since!