what size are the speakers in this truck?
crutchfield.com has a listing of all sizes in all makes
if there's speakers in the doors they're 6.5 inch, if on the dash they're 4x6 inch. if it's an extended cab i think the rear speakers were 4x10 inch but dont quote me on that. if regular cab, rear speakers are 4x6 inch.
my truck is a 95 and it has 6.5" in the front doors, and 4"x6" in the back.
Front door: 6.5" Rear Pannel: 3.5" or 4" work http://www.crutchfield.com/m_399/Car-Speakers.html?tp=12
if they are the same as 1990 6x9 and you might have to drill new holes it all depends on what you are trying to do
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