Re: installing speakers in 02 explorer
Door panels are easy to remove. Most likely, your speakers are mounted to the door itself, behind the panels, so yes- you'll need to remove the panels.
It's easy- just find the screws holding on your armrest. Remove those. If you have power windows/locks, disconnect the harnesses (should be one or two clips on them or actual screws). If they're manual, pop off the window crank. Unscrew the plastic lock (if it protrudes through the top of the panel. Now, all you should have is the door panel retainer clips which pop out by pulling on the panel. If you want to be extra careful, go spend $10 on a door panel retainer remover. It looks like a prybar.
Reverse the process to re-install. For the retainer clips, make sure they're aligned over the holes and give them a good swat with the side of your fist.
It's too easy of a job to pay someone else to do.