The power amp of my 'line has been removed by the previous owner, leaving the 4 channel RCA wiring loom and the speaker wires dangling in the boot. The speaker wires I'm OK with, but is there any standardised colour coding for the RCA plugs? The head unit is a Kenwood MJ919/D919, but without pulling that out, is there a way I can sort out the 4 RCA plugs for the new power amp?