I have a 1999 grand prix gtp. Originally the car had a factory cassette player and 4 ohm speakers. I swapped the radio out and now it has the cd player with the equalizer. Im wondering if this radio is supposed to have the 4 or 8 ohm speakers? I have a set of 8 ohm speakers from another grand prix and a set of 4 ohm speakers from a early '90's lumina euro. Will it matter which speakers I use? Which ones will sound better? Thanks for the help.