Lift the seat to the upright position.
Use the wrench to remove the John Deere's negative battery cable.
Pinch the tabs on the plastic wiring harness to unplug the safety seat switch.
Loosen and remove the plastic adjustment knobs on the bottom of the seat track. Also use a wrench to remove the two metal retaining bolts mounting the seat to the seat track. Set the old seat aside.
Line up the bottom of the new seat with the track, slide the two retaining bolts through the holes on each and tighten the bolts using the wrench. Adjust the seat to the the length you want by sliding it along the seat track, then tighten the plastic adjustment bolts.
Plug the wiring harness into the neutral safety seat switch mounted at the bottom of the new seat. If, for whatever reason, your new seat does not have a new seat switch, use a screwdriver to remove the old switch from the bottom of the old seat and mount it onto the new seat.
Slip the negative battery cable back on and tighten it with the wrench.