im wireing up my alpine HU in my van and it says there should be a ignition wire and a wire that goes to the battery. i have a wire that goes to the fuse is this the battery wire or ignition? would it be a good idea to have a fuse on the battery cable? unless the 1 that already goes to the fuse is the battery cable? i have some wires hanging there one is grey and 1 is orange i dont know what theses are. the van had a system in it previously and now the wires are all over. and there is some hangin there from a switch that was torn apart that was located near the radio.