My S4 avant left the factory with the full Bose setup but when i bought it it was/is missing the amp, sub, CD changer and all the brackets/moldings i.e everything from the boot.
I am now trying to replace everything but all the amps i see on ebay have a long thin plug socket but the wires in my boot have two square plugs. Is there a wire that goes between them? does any one have a pic of all the parts i need or all the part numbers for an 1999 avant.

Any info welcome