fox body speaker sizes?

Unless you are installing amps and such, you don't need the expensive one's with the big magnets. For best results, you want things to match, kind of like other things. I had some infinities in 6.5 in the front and dash and some leftover 5x7" Cirwin Vegas in the rear left over from my old car. Sounded pretty good, ten times better than stock. Of corse since I deleted the radio system they are just sitting in a box. I am not sure what to do with it all.
 
Like the rest of these guys, I've always been a fan of Infinity and Alpine stuff.

BTW what head unit do you have in and how many watts is that pushing? This always makes a huge difference in what speakers will sound the best.
 
I'll have to jump on the Kappa bandwagon. With an amp and subs to handle the lows, it'll sound great. I get compliments on my stereo constantly, not becuase its the bassiest, but becuase everyone remarks on the clarity and precision that it produces.
Kappas will also fit in every opening using 6-1/2's in the front. The speakers also come with an inline crossover that helps clarity.
If you check crutchfield and other online sites you can probably find them cheap