Older TJs radios have square corners, newer ones have round corners. The connectors are different, too. If you look at a factory parts list for your Jeep, it will list radios for your year. There is a three letter model, i.e. RAD, RBK, RBY, REK, RBT, RBQ RB3. Older square corner models are RBR,RAS,RBJ RBA and RBL. Then there is a part number for your year Jeep. The part number indicates features specific to your Jeep like the backlight color.
These models are used in other Chrysler products, and they wil fit and work in a TJ.