Good advise above. Just imagine those little salt crystals waiting for a nice humid summer day to resume their work! It's impossible to even begin to imagine where or what 'might' be left that's good. Failure, of course, will be at a most inopportune moment. Replace it all now. Doing it all at once will give you the chance to run things differently, if you desire, and add things for the future. I ran mine in conduit just for the heck of it.
Automobiles that get flooded with salt water, brackish or 1.026, are automatically totalled by the insurance companies. They've had long experience with such things and been bitten too many times. I don't particularly care for insurance companies, but must admit, that when it comes to actuarial issues they've got the sharpest pencil in the drawer. I would follow their lead and rewire, right down to the nav lights.