Lighting Help

Hi, I have a 2004 Blazer ZR2 (4x4 vin X) and just installed a set of aftermarket foglights. To make them legal i installed another relay that is normally on and will switch off when energized. Problem is, the headlights on this truck are negatively switched. Anyone know where i can tap off to get power for the relay when the high beams are on

If i understand this correctly you could use another relay to reverse the voltage--if you want it to activate on a negative switch hook that up to the coil and hook up +12V to the other side of the coil and common. Or could you change it so the relay is N/C and activates when it sees ground?