6x9 speakers

How about it has anyone installed 6x9 speakers in their doors? I thinking about some polk mm691 shallow mount. Any sugestions? I want to keep the factory radio just upgrade the speakers.

You'd either have to do a lot of cutting, or build a surface mount box in place of the door pocket. The latter has been done, but I don't remember the former.

I did the same upgrade with Polk 6.5" round speakers. I don't think that there would be enough of a performance enhancement with the 6x9's to make it worth the extra hassle, but that's just my opinion.