I suggest you do some reading here is a great site
http://www.the12volt.com/caraudio/caraudio.asp . You will need to see what gauge wire to run from the batt to the amp. You will need to install a fuse less than 12in from battery as if there is a short your carpet will catch on fire if its not fused by batt and amp. If you want better sound use the 4 channel amp to power the front,back speaker and get a mono amp that has bass boost knob for the sub. If you have the double din for your radio, an equalizer and radio will be an excellent option. With a 3 channel equalizer you will not need the bass knob .