I recently replaced the stock speakers in my 08 with these Infinity’s. They were $50 and sound great. Amazon says they don’t fit but they do. The reason I’m sharing is because they have an adaptor ring that mates almost perfectly with the stock speakers location. There are a couple of tabs that required a bit to filed off but nothing major. It could also be the case that they require no mods, I just sanded them to be safe.

 

Also, I added a thin strip of butyl rubber under the adaptor and under the speaker before mounting to ensure a vibration free connection and add rigidity to set up. If you don't have butyl rubber you can also use "rope caulk" sold at any hardware store store.

 

I made adapter rings out of my factory Alpine speakers that were dead (the classic re-solder of the voice coil leads didn't take) by cutting out the cone and cutting the arms that held the magnet and voice coil. That left a ring that will fit any 6.5-inch speaker, and of course mounts absolutely properly to the door. All I had to do was drill holes for the screw to hold the new speaker, then mount it back in and connect.

 

Hey, thats a really good idea!