System - Good Ground

Ok i just finished my system in my car but i am getting some pretty bad engine noise.....i am goign to check my cables and make sure that the RCA are away from any power cables....but also i would like to make sure the ground i am using is good. I have a 2001 GP GT.

where is a good place to put the ground wire in the GT?

there's two bolts just behind the back seat, between the speaker and seat, on that little lip. thats the ground i'm using without problems.

is the noise there all the time? with my system i get some feed back at low volume and higher rpm's due to the fuel pump. there's a tsb on it but i've just never taken the time to research it cause crank the bass up a lil and you can't hear it.