By the way, if you're replacing speakers & looking for better sound quality...
Forget about installing them back in the rear hatch.
I moved mine to the rear doors (5.25" was as big as I could get to fit) and the bass response drastically improved. Tried the same speaks in the hatch at first, but was very unhappy wth the way they sounded. Once I moved them to the doors, it was like I had installed a completely different type of speaker!
You will have to do a bit of sheet metal trimming to get them to fit in the doors though.