A heat gun will loosen the glue where the tube attaches to the connector
threads. Or boil in water for 15-20 minutes.
Thread the atty onto a broken battery or an old battery connector that is held in pliers. Wiggle them against each other and they should come apart. The wires are soldered to the connector. Try not to separate them, they are a pain to solder back on.
Depending on the manufacturer you may be able to then insert a brass tube that will fit inside the barrel and push the works out the bottom.