It has been asked many times... 
Front and rears are 6.5 inches, so 5 1/4 fit, with space to spare.
The things to keep in mind are that the rears do not have a lot of front clearance, so Crutchfield marks many speakers with as not fitting which do (case in point the Polk db650 I put in last autumn...). Also, the bolt pattern on the OEM speakers is not standard, so you either need an adaptor or to choose speakers that have that pattern (don't what know do, mine don't...).
There are also tweeters up front, but Crutchfield does not offer to match those.
Hope this helps,
Nicolas
Front and rears are 6.5 inches, so 5 1/4 fit, with space to spare.
The things to keep in mind are that the rears do not have a lot of front clearance, so Crutchfield marks many speakers with as not fitting which do (case in point the Polk db650 I put in last autumn...). Also, the bolt pattern on the OEM speakers is not standard, so you either need an adaptor or to choose speakers that have that pattern (don't what know do, mine don't...).
There are also tweeters up front, but Crutchfield does not offer to match those.
Hope this helps,
Nicolas