It is very much so possible to do. And all advice is correct, you are on the right track. The only thing I don't see mentioned that you will want to (and may have to) do based on the usage of the additional battery, especially being another 12V, is you may need to change your alternator to one with a higher amp output. Your truck will see both batteries and will consider them as 1. So in order to keep the 2nd battery charged, you need the output from the alternator to compensate for the added power usage. I did this to my Ford, running a winch and TV etc... on the 2nd battery and all I did was duplicated the alt to battery connection, and the necessary wiring and fuses to the additional electronics. As far as possibly needing to use 1 battery to jump the other, just use jumper cables LOL. You'll be simultaneously charging so you wont have to drain 1, and or just swap out the pos./neg. of each battery to run the car with the good one, while the other charges. Any rate im rambling on now. So yes its possible to do it, good luck and enjoy it.