I have no experience with sportcoupe but i've<br> upgraded my sound system in the Cwagon (factory<br> non-bose). I think that besides fact that the<br> rear speakers are not mounted in the doors, there<br> should be no big difference.<br> <br> All the speakers in new C including front and<br> rears are custom speakers and its plastic<br> housing is integrated with element that holds<br> it to the body. So that means there is no direct<br> replacement for factory speakers because anything<br> else won't fit in place or even if it fits there<br> will be a large gap between speaker and its<br> grille which will make system accoustically<br> worthless.<br> <br> What i did? I've destroyed factory speakers, making sort of 'adapters' of them (removing<br> magnet, cones, membranes and all the stuff - only<br> the outer plastic ring remains) and then mounted<br> Brax/Helix speakers on them. Good sealing is<br> critical. It was a first step of my audio upgrade<br> but it sounded decent after that.<br> <br> Factory speakers are 6.5' front and rears 5.25.<br> <br> Then i decided to add 3-channel amp and subwoofer.<br> Email me if you want any details.