The first thing that you need to understand is that amplifier is overrated. Take any power rating that they list for it and you might actually get 1/3 of that. If you are lucky.
Alright I should take amp bAck ! what amp and speakers are best for 01 chevy ext cab subwoofers under backseat 2 front speakers in doors eventually adding total 6 speakers I like loud clean sounding heavy metal