Google the HK model, there's bound to be a wiring diagram online...it's only a radio so not that many wires [power, earth from chassis, amp in, speakers x 4/6/8, steering volume etc,...] and most follow std cable pin out.
If it's the one with sat nav, there's a CD changer under the seat and an amp in the boot, under the flap in the floor.
Iso connectors fairly standard, it's if you want to use the original amp it would need the extra signal to turn it on.