My '01 Limited had a blown subwoofer speaker when I got it. You have to remove the plastic interior panel to get to it. It wasn't difficult, just a bit tedious. I didn't need a manual, although you can get the procedure easily enough by googling this. Basically, I had to remove the left side of the rear floor to get at the attachments for that panel. It was simply a matter of just following the fasteners and experimenting a bit.

The speaker itself had a torn cone. You could pull it out and then try to match a replacement, but mine was easily repaired and my fix has lasted several years with no problems.