I threw these in an old Corolla - they didn't fit *quite* right but my buddy helped me get these to fit. I think we not only screwed them in but used industrial caulking to keep them in place. Either way, they were MUCH better sounding over the OEM speakers my hunk of junk came with. I'm not a sound guy, so as long as it sounded "better" than the older ones, I was happy. I wish I could provide you with some detail, but like I said I just bought speakers I figured would fit and my friend, who is quite mechanically inclined, helped me install them.