Need HELP on Pro-ject Tube Box SE II

I bought a Pro-Ject Tube Box SE II and I want to change out the two tube with different tube. I got the 2 tube out but I can't get the round heat sink/vibration off the tube. Has anyone done this before? I need help on seperating the two. Thanks...
They don't come apart. Congrats on getting the tubes out without destroying them altogether. I replaced the stock tubes with Black Sable Tung Sols and got much better results.
Thanks Chayro..
I got the dampen/heat sink off the stock tube and replace it with Telefunken tubes. My TT got ship for repair so I have not test out the tubes. I will let you know the results.