I've got a 2005 Double Cab with the in bed 100w/400w inverter. Is there any way to rig it to be on all the time at the 400w capacity without the key or the motor running. I'm not worried about a dead battery as I can always get a jump. I'd just like to be able to run a few things in peace and quiet at night without leaving the keys in the ignition. I'm sure that somewhere on here is a write up, but I've been unable to locate it. Thanks for any assistance.