98 Passport speaker sizes?

So my old stock speakers are starting to crap out on me and I plan on buying some new aftermarket ones that will fit. I have measured the front and rear but came up with different sizes then stores such as Best Buy, Crutchfield, etc. These stores also tell me different sizes from eachother. If anyone knows the right size speakers dimensions for front and back please let me know?

Thanks,
Micah

So my old stock speakers are starting to crap out on me and I plan on buying some new aftermarket ones that will fit. I have measured the front and rear but came up with different sizes then stores such as Best Buy, Crutchfield, etc. These stores also tell me different sizes from eachother. If anyone knows the right size speakers dimensions for front and back please let me know?

Thanks,
Micah

use crutchfield.com -> car speakers
http://www.crutchfield.com/cgi-bin/autoinfo/autoinfo.asp?sl=Y&vb=Y&lp=%2fApp%2fProduct%2fCategory%2fGroupMenu.aspx%3f g%3d399%26c%3d3%26tp%3d12
and you can select your car exact model. The front and rear speakers side are different I think. That site is pretty accurate.
Good luck

-Ken