Adding a Passenger Airbag Disable Switch to an F250

Have you thought about a full size van like an E350? You don't say what ages the kids are but they grow fast, and 3 in the front gets old quick on a long trip. A van with the right drivetrain will tow as much as a pickup. If you're buying used, another option would be an Excursion. Let mama sit up front and have two rear rows for the kids.