[ls1nova71]

Yeah, for the cruise to work, I'm pretty sure you need both of them hooked up. There are certain parameters that need to be met each ignition cycle for the cruise to work and its those two wires that it uses to make sure the brake switch is functioning correctly. On a manual transmission that wire would be hooked up to a clutch pedal switch so that when you push in the clutch it disengages the cruise, otherwise it will likley bounce off the rev limiter when you push in the clutch. You can hook it to the brake light switch though as long as you remember to shut the cruise off before using the clutch pedal.