Help with my Pro-Ject Tonearm.

I had a accident the other day, my Pro-Ject 2.9 got knocked off its shelf. Some slight damage to the wood body due to the platter coming loose and I had to re-solder the RCA jacks in back, they took the brunt of the damage. The tube of the arm sits in an oval metal ring on 2 points resting on a threaded stud with 2 little holes running parallel on top of the stud that go through the oval ring. You have to look at your arm to know what I'm talking about. The tube is not resting securely in those studs now and I would like to know how I can secure the points inside the oval ring to their place in the threaded studs?