I have an '03 Pontiac Vibe with the standard 4-speaker system. I've got an aftermarket deck, just got a pair of 6.5 3-ways for the rear doors, going to get an amp any day now. I'm looking for the OEM trim and brace for tweeters (or alternatively some information on how to do it myself) and for the monsoon sub enclosure and trim.
Are you going to keep the stock speakers in the front door and upgrade the rears to components?
There was never an option for components in the rear, only the front. To install in the rear you can just use the enclosure pieces that come with your speakers and either do a flush (drill hole into door panel big enough for tweeter and enclosure) or surface mount (tweeter sits on top of the door and enclosure is only held on to door by a screw or two).
To upgrade the fronts to component you can do the same thing (flush or surface) or buy the M&T sail panels that can hide the tweeters.