It depends on what size cab u have. I have an 89 regular cab and I only have one pair of speakers, they're 6.5" in the door speakers. I'm pretty sure that extended cabs have 6.5" up front and 5x7 in the rear
6.5
5x7 6x8
Both the front door speakers and the speakers in the rear are standard Ford 6"x8".
The speakers in the doors of a 1991 Ford Ranger are 6-inch speakers.
6 X 8
if i am not mistaken the front door speakers are 6 in a half inch and the back speakers are 6x8 inch speakers.
from80's to 98 its a 6x8 in front and back
i believe they are 6x81/2 or 6x8.5
5x7
front speakers are located in the door panels. the size is 6x8 or 5x7
6X8 most speakers are 6X9, pioneer makes a factory replacement for Ford/Mazda that is 6X8
i know the measurement is six and half but that's all i got.