[Tdragone]

Start with this:

Open door + rear if you have the extended cab.

pop up the plastic trim piece between door and carpet, then remove the one or two screws that hold the plastic cover surrounding the Parking brake/hood release.

Now you can pull up the carpet on the drivers side.

In my (2002) there are a few grommets in the front wheel well area that I noticed when running a 2 gauge cable for my amp.

Maybe one of thise is woor/ripped/missing?

Good luck..

Maybe put a sprinkler (or have a friend) spray water to try to find it?

The plastic wheel well cover pops out after removing the plastic expanding grommets. There's a slot for you to get a screwdriver into to pop the head of the grommet out; and then the body will come out. Take that off and look in wheel well for things that look out of the ordinary.