KMC,
Not sure about the club cab, but the quad seats have the shoulder harness built into the seat back and the seat hinges (seat back to base) are more stout to handle stresses from impacts and flying bodies. Also, mounting to the floor may be more robust for the same reason. I don't know if, in a regular cab, the harness is built into the body work or still part of the seat.
Just something to consider.
JK