+1 to Ron. Class D is the way to go in these Z cars due to the tight install locations. I burned up a MTX Class A/B amp mounted under passenger seat that even had a fan on it. Now have a Rockford 4 CH Class D(smaller footprint/more power) and it barely creates any heat at high volume levels. Stay away from BOSS, due to their lack of quality/reputation. You get what you pay for.
I like the PN1.650D better due to the sturdier connections for power/output. The below link is very reputable and will save you lots of cash over Crutchfield.
Soundstream PN1.650D Picasso Nano 650W Class-D Monoblock Amplifier
Don't forget a quality 4ga amp wiring kit!