well my factory 4x10s were kinda neat for a while when i first got my monte, cause they just sounded like old stock speakers did new. well after hitting the volume up a little to high a few times in the past year, they just plain suck now. so i am thinking of upgrading to 6x9s in the rear. ive done research and found adaptors and what not to fit them in but i dont like the way they would sit and just dangle like stocks, seems it would just lose so much sound in all that open space. i dont want to hack up my package tray either. so my though was to to build basically to speaker boxes that mount to the under side of the package tray, set the speaker insid the box facing up through factory 4x10 opening. i dont quite know how to explain, it just was a thought that kind jumped at me this morning randomly. ited basically be a box with no top, the speaker would go into the box and be mounted on 4 little pedstals within the box, then the whole box would be mounted up to the metal under the tray. i know the speaker wouldnt be optimally placed and it sounds like a bulky cob knobbed mess, but i would improve on it as i go i think. even though the speaker would be a little lower than factory from the factory mount, it would have semi enclosure to help force sound. if anyones got any input or opinions i d love to hear it. i think i may try and accomplish this tommorow