There are past threads you can search for that deal with both removing the sliding cargo tray and installing one on a car that didn't come with one. There were a few trades involved from folks that didn't like their trays and folks that wanted one. I don't know of anyone who tried to buy one from a dealer. Installing a tray in a vehicle required some modification to the bare floor for the hardware locations to work. Non tray vehicles didn't have some of the holes for the hardware as I remember. I don't know about compatibility between 4Runners of different years.