OK fellas, i have a 97 A4 with a Gamma head unit. Looking to put a CDA9831R in and just wondered what else i need. Obviously i need the two infill bits for either side of it, are there different quality ones available? Want ti to look as good as it can tbh. Do i need any form of wiring adaptor? Someone said i would need a "link cable" (?) as the rear speakers are amped. Is this correct?