I have Sony 5-1/4" in the front doors of my '89 245 wagon. The door panel is a compressed wood/fibre product. It did not hold up too well to repeated door closings. What I did was I cut a donut shaped piece of plastic and slid that behind the door panel through he hinge side. This gave me better anchoring behind the cutout of the speaker. THe metal screw clips that came w/ the speakers were useless with the OEM door panel and kept tearing the panel. I installed these speakers with very little cutting to the existing speaker holes. In the wagon's rear cargo area, I installed 6x9's on the removable side covers. If you want, you can install 4" near the back rests of the rear seats. Be careful though if speakers are not there now and you have to cut through the plastic near the pillar and make sure you know where to cut. Best of luck and enjoy the dramatic improvement in sound!