Upgrading a Car's audio is the first thing you Do! (if you have a clue!)
96 GT with:
JVC KD-SH99 Head Unit... rotating Faceplate, plays MP3 cdroms... any
Fronts: Polk 2-way 120Watt speakers
Rear: Sony 3-way 100 Watt speakrs
Trunk: MTX 10", Blue Thunder enclosure
Amps: Sony 4-channel, 100w/chan, with crossover
Amp2: Sony 2chan, 40watt rms('95, but quite good!)
Assorted: street wires, monster cable, Power Noise filters, antenna noise filter, etc.
Notes: Running RCA cables from HU to Amps in back is a bitch. Have to take rear seat completely out. One amp mounted under rear deck, other mounted on bowl, in center of spare!(dont laugh, it works great!).
Oh, and get used to ripping the dash out, to "twiddle" with the HU. it happens a lot.... removing door trim for front speaks is a breeze.
what HU you doing?
and speakers ARE THE MOST IMPORTANT PART btw!!!