What size are the front/rear speakers? 6.5" ?

Also, how do I get the panelling off the front door so I can replace the speaker.

I have a 91 accord SE

 

To pull the door, remove one screw behind the door handle. Another screw doen in th 'cup' that you hold when shutting the door. There should one or two screws under plastic covers above the speaker grille. Another one towards the back of the door, down by the light. It should also have a plastic cover on it. I think that's it, then pull out to release the clips and lift the door panel up.
Your car may have a four inch speaker mounted to a big black plastic baffle. Take this baffle off (three or four screws) and you will be left with the standard 6.5 inch hole. You will probably need a spacer if your speaker has a large magnet. Good luck.