Dont forget to mig weld a bolt to the chassis as close to the amp as possible and use "heavy" cable for the ground.I have seen many dodgy installations where the installers use a self tapper.When it does come loose the next ground is your front loader...which will be toast!I run 400+400wrms in both of my cars, at 130 x 2 it is mind blowing as i use hi fi 10's and fane compression'sThe frontloader runs the original car speakers..phoenix gold 6.5 x 4.PS dont forget to use a HQ battery in the mobile..I swear by Varta from germany, they can handle it and last up to 10 years.You may been to up your alternator unless you have a high current bosch.