Well, I found this posted by Kodiakz in regards to a 2003 speaker question.
"The fronts will accomodate 6" drivers direct drop in. The rears are actually 5.25, but can easily be modified for 6". "
Not sure if it helps you much. If you are ordering from Crutchfield, they are pretty good about getting things right. If they screw up and recommend something that does not fit, they should happily rectify the situation.