Because of the extreme sizes of the radii in question I approx'ed the bearing circles as square:
Data:
* Mass of belt: $2.39 \times 10^{21}$ kg (Google)
* Density of belt: roughly $2.1 g/cm^3$ (Wiki of Ceres)
* Radii of the needed bearings: the chart in the talk section.
If we assume that the bearings have radii of $r$ meters, then the volume of the cubes surrounding the bearings will be $2\pi \times total \space radius \times r^2$, and the volume of the bearings will be $\dfrac{\pi}6 \times 2\pi \times total \space radius \times r^2=\dfrac{\pi^2}3 \times total \space radius \times r^2$.
The volume should be: $\dfrac{mass}{density}=\dfrac{2.39 \times 10^{21}kg}{2.1g/cm^3}=1.14 \times 10^{18} m^3$.
Throwing in the numbers from the chart:
$$total \space radius=(83+129+189+504+1107+2154+3684) \times 10^6 km=7.85 \times 10^{12} m$$
Which gives:
$$2.58 \times 10^{13}m \times r^2=1.14 \times 10^{18} m^3$$
$$r=210.2 m$$
Which should be enough.