[Charlie57]

It's time to get an updated system in the 98. What size are the speakers in the doors? Crutchfield says 5 x 8 fits in the door and rear deck. I am planning on going with four Kenwood KFC C6894PS. Kenwood Excelon KDC X696 head unit and a Alpine MRP F-300 amp.
Thanks,
Charlie

 

[carbuff]

Sounds like you have all your info correct. My 98 had the premium sound and not the mach 460 so swapping out the head unit was pretty easy. I only had to ditch the one crappy amp in back of the head unit. I ignored all the amp wiring by unplugging the amp harness so I could use the basic adapter plugs for power and speakers. Pretty much plug and play. Mach 460 is a bit more complicated with the tweeters and all. I will be replacing my speakers in the spring as my car is stored for the winter. Ill probably go with kenwoods too.

 

[metalman302]

Factory is 6x8 but the "6" is smaller than a normal 6x9. There are not many options for true 6x8s but there are plenty of 5x7s which have elongated tabs to be compatible with a 6x8 hole.

 

[LilOnesMustang]

5X7 or 6X8 Fit my 99 mustang. I just finished changing out all the speakers in my car about 2 hours ago. Was real easy besides getting the screws out/back in on the back 2. Gotta have the weird shaped screw driver to do them. Anyways, I got mine from Walmart. They are AWESOME!! I got these -
Scosche HD57683 - 5" x 7" / 6" x 8" 3-Way Car Speakers (Pair): Auto Electronics : Walmart.com

They were only $29.99 in my actual Walmart store. The sound is great with my Sony Xplod Cd player. I turn the volume up to 5 or 6 and thats loud enough! Hope this helps

BTW just in case you don't know, the 6X9s WONT fit without modding your speaker hole. They are to wide. I screwed up and purchased those first thinking there couldn't be much difference, but there is. Good luck!