I am installing a dual battery setup in my 04 Expedition EB. I am going to run all my aftermarket electronics from the second battery, to protect the primary battery. I need to get a few 14 gauge wires from the battery to inside the Expy. I am installing a aux fuse panel behind the glove box, so that is where the wires from the battery need to get to. I know there are a lot of existing rubber boots in the firewall, but I could not easily find where they entered the inside. If you have run wires from the engine bay to the inside, what rubber boot did you use and where does it come out inside. What trim panels did you remove to see where it came inside? Thanks.

 

Things to think about.
What will be your current draw for your electronics, and are you sure you just can't replace your current battery with one with a higher reserve AMP rating? If you plan on connecting the batteries in a parallel circuit, you can still draw both down. If not, how do you plan on recharging the secondary battery? You may run into charging trouble from your alternator.

 

Thanks, but none of this is an issue. I have it all covered and have done it on several vehicles. I just need advice on getting the wire into the cab.