Dual Battery setup

[PARAGON]

Has anyone done a dual-battery setup yet. If so, where did you locate the new battery.

I've got several things backed up that I have been needing to do and have parts everywhere. I plan on adding the Pioneer adapter setup for adding my MP3 player and XM satellite, I have a 1200 watt inverter I am adding, I have a hands free kit for my Motorola phone, I have a portable DVD/VHS setup that I want to make easier to plug up, I am setting up so my notebook will read from the Garmin GPS, installing Cibie Tangos in the DRL location, etc.

I have already run the battery down as the cigarette lighter plugs are always hot and are not protected against the battery run down feature like the lights are. So, I think I am going to add another solenoid that's switched like the winch setup that will power on/off all of the lighter plugs (except for maybe 1 or 2), other hardwired electronics and the power inverter.

I think more available amps would be logical with the addition of the new electronics, especially since some of the stuff is left on after the ignition is off.

Thoughts?