just run another wire, make sure you put a fuse inline. The constant wire should be the yellow one. Use something around 14 or 16 AWG wire, and use a 15A fuse. Try and connect it directly to the battery. If you connect it to another wire from the fuse block that has constant power, you risk burning up the fusible link in the engine. If you dont know what fusible link it, its like a fuse, expect when it blows, unlike a fuse, the wire burns up, and you need to replace a section of a wire.