I'm going to install a new head unit in my 91 extended cab. How does the trim around the radio and A/C controls come off? What size speakers fit in the doors? The only speakers I have are in the factory door locations. Can speakers be mounted in the rear of the truck, maybe in the side panels of the extended cab? Are there mounting holes behind the panels for speakers?

 

Trim piece just pulls off. Door speakers are 6.5". I don't know if there are mounting points in the rear or not, but you could certainly mount some 6x9 boxes in the rear if you wanted. That would likely be the easiest method, and wouldn't involve cutting a hole in the plastic trim.

 

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