I just purchased a pair of Polk Audio DB521 speakers. I've only taken them out of the box to test fit them in my car when I learned that one of the previous owners had enlarged the speaker cutouts to the point that these 5 1/4" speakers have no where to mount. I'm going to have to remount the current speakers for the time being. From what I've read in the Electronics section here, these should have been drop-in replacements for the stock rear spearkers.
I'd like to get $65+shipping for them, but I'm open to offers.
Here is link to the manufacturers website.Polk Audio DB521