OK sio I had posted this in the wrong place so starting over . I have the premium cassette with six speakers and the amp under the pass seat . So I've been reading on here a bit and found out I do have premium sound cassette . Door speakers and amp under the pass seat . So all speakers are 6ohm except the dash which are 3.5 . Are there any upgrades for the speakers . They don't sound bad , no cracking or weird noises or anything . But I would like to get better sound . I did read "Installation of OEM 1993 Premium sound stereo into 87-92 Mustang " on here and great info . I had already wanted to get the cd slave to add on which are easier to find and am glad to know there is a difference in the face plates . Round vs square which my car has . I know adding 4ohm speakers will overheat the amp and leave me with nothing . Also running more efficient speakers will give you better sound w/o having to overpower . Not finding 6ohm and would 8ohm speakers produce lower levels of sound ? Any better speakers from another Ford that would work or should I use 8ohm . The 8ohm speakers are more money but no biggie . I guess I can run 4ohm in the dash . Some good 2ohm speakers that say they combine with your speaker wire to produce 4ohm load and over 90db sensitivity with 25rms and 75w max . No need for more than that . Are the 6x8 94-04 Mustang premium sound speakers the same ohm's ? I think I'll try searching this next . All the 6x8's are the same #'s F4ZF-18971-CA . So they are the same just newer and possible in better condition . The plugs may or may not be different . Might have changed after 94 . MACH 460 speakers 94-2004 for the doors 4x6 may work for the rear as well but the last two letters are AA and they look much deeper . Maybe too deep . The AA are 8x5 3/4 so will not fit . Don't want to get to crazy here . Hoping to get a CD slave or equalizer if possible afterwards .