After reading the other reviews I agree to most,,, this product needs to be redesigned, Dorman should ge on the stick with this one, It arrived asembled and it must be disaembled to install, the 2 doors/ flaps are extremely hard to slide off , I had to rest the asembly in my bench vise gently without damaging it and then tap the shaft out with a long thin rod, I then had to SAND down the shft , full legnth with medium sand paper enough to let the 2 doors/ flaps slide back on with only SOME resistance,,the shaft has 2 flat sides to it so the doors wont pivot or spin around it, FURTHERMORE the great Dorman Idea about the Metal pin fell out of its hole Duh??? It is too loose that it does not stay in the hole, I put the pin into my bench vice lightly and tapped it to the side to bend it very slightly,, then tapped it bck into the hole in the side of the shaft, so resistance holds it in, DUHH??, it now is tight,,, I will contact the seller about this too,, I will add to this after I install it in the 2001 Jeep Grand Cherokee with dual zone controls that will be 1 zone after.//////// UPDATE/// I installed this retro fit item and it worked great, be VERY careful removing the actuator motor without breaking anything,wigle it off, then I used a Dremel cutting wheel to cut the heater box in the RIGHT areas along with a hack saw blade,,,Do NOT get close to the Airconditioner core on the right,, The bottem edge is on just by a Tounge and Grove slot and after cutting the top and Left and Right sides it comes out easy,, DO NOT accidentally cut into the wires for the motor,,USE THE INSTRUCTIONS PICTURES OR YOUTUBE VIDEOS,, Pull the old white plastic piece out with a pliers, then remove the closest door then cut the center divider wall out and be carefull at its bottom where the new axle shaft will be still SUPPORTED at its center,,then remove the far door, all were broken,, Then install the new far door ,then the new shaft thru the the box into the close door , along the center divider area then into the far door and the far door slides onto the very very far small shaft of the original Passenger side motor,, all still spins easy,, then to test it, put the motor on the outer end of the new shaft,, keep the little metal pin between the 2 plastic "stops" ,, Then plug in the wire ,start the Jeep and TEST the movement of the new doors, ONLY the Driver side control will work both doors,, ALL OK? then remove the motor again and reposition the original plastic pannel that you cut out at first, the metalic tape is like tin foil and works great, cut a bunch of short lengths ad make it air tight,, reassemble all back as a finished unit and you are all set !!! I did mine in 25'F outside temps and took almost 2 hrs because it was the 1st time,,, now as an EXPERT I can do it in an hr,, I took picture to show the Jeep Grand Cherokee's owner and he was thrilled. Read more