I am thinking about replacing the speakers in my 2001 Toyota highlander. It has the JBL system with a factory amp. I can't find any information on the factory amp and googling the speaker product numbers is no help. Would hooking up new speakers to the factory amp be a bad thing or would the speakers just be underpowered. I would leave the mounting brackets and just attatch the speakers to the mounting bracket terminals that lead out to the amp.

The number on the back of my speakers is: 86160-0W110 if any one knows the specs of these please share. The size is 6 1/2.

I am also in the dark about the factory amp and have no clue on its specs. Would anyone be able to shed some light on its specs?