As long it's a four wire pickup, or four plus casing earth, then two wires are for one coil (green and red) and two for the other coil (black and white). Most aftermarket humbuckers come with the red and white wire joined, you use the black (ground) and green (hot) wires to make your connections, this is in series. A proper Musicman humbucker is in parallel so you use all four wires joined in pairs to make you connections, green and white (ground), red and black (hot).
Or wire it through a push/pull pot so you can switch between series and parallel. A humbucker wired in parallel, roughly speaking, will be brighter but around 30% lower in output than it wired in series.