In my opinion, depending on how powerful the subs are, I'd spend the money on some nice speakers for the front doors and keep the back speakers stock...I've found that the low frequencies from the subs tend to drown out the sound from the rear speakers

'95 LX ATX Midnight Blue
Pioneer 7300 in the dash
Pioneer 6x8 180w 3 ways
2 RF Punch 12's in plexi bandpass
Pyramid 800w 2 channel amp

K&N Filter
Custom Dual Outlet Tip
Removed resonator
Strobes in the head/tail lights
Bosch platinum spark plugs
Carbon fiber HVAC panel
Pilot fog lights
Super white interior lights