I measured the main speaker at approximately 5" and the smaller speaker at approximately 2".
Here are the removal instructions for the door panel:
Front Door Panel Removal / Installation
Small flathead screwdriver
medium to large Phillips screwdriver
T-15 Torx bit
Install / removal based on a 1995 SSEi Bonneville
If the window control switch is removed from a door the main drivers window control will no longer work for that door.
Reverse process for installation
1. Remove the white door light by carefully prying it out with a small flathead screwdriver from the rear most side. Disconnect the power connection that the light uses and place the light off to the side.
2. Remove the two Phillips head screws located at either end of the light opening.
3. Using a small flathead screwdriver remove the plastic cover located at the top of the armrest handle. This is the piece with the small light that shines down on the door controls. You should be able to pry it off from the top edge fairly easily. Once off, disconnect the electrical connection and place the piece to the side.
4. Remove the Phillips head screw from the opening.
5. Remove the door controls by carefully prying them up with a small screwdriver. Careful when you do this because there is a clip on either end that is used to hold this piece in place. Make sure you do not loose these or it may not stay in very well later. Disconnect the electrical connections and put the controls to the side.
6. Using a 7mm socket, remove the bolt located at the front most lower corner of the door panel and the bolt a few inches above it. Both are located on the outer edge of the speaker / door pocket molding.
7. Remove the center cap behind the door handle with the small flatheat screwdriver.
8. Remove the screw behind the handle using a T-15 Torx bit. Carefully remove the molding behind the handle. This may take a bit of manuvering to do. Be carefull too since there is a wire rod that goes thru the door lock and can be tricky to remove. The rod snaps into place in the lock handle and the rod does turn out into the extended portion of the lock lever. The door lock will not pull thru the opening in the molding so don't try or you'll break it.
9. Pry the door panel loose by CAREFULLY pulling out the push in clips that line the front, bottom, and rear edges of the door panel. This can be done by carefully prying the panel up using a flathead screwdriver or a some other flat and stiff object. Work your way around slowly and be sure not to put too much preassure on the parts since the panel can crack and there are components behind the door that can be damaged.
10. Look behind the panel and disconnect any other connections such as the speaker connections.
11. Once all the screws, clips, and electrical connections have been removed, lift up on the panel and slowly work it out of the track that it sits in at the top edge. Don't force the panel or you may seperate the door panel from the trim work where it is attached. It is a slide in fitting at the top edge but it is generally a tight fit, especiall if it hasn't been removed before.