The octagonal socket should be available from Robb at British Tool -
> Replacing the bearings is a bit of a job. One nut is RH thread, the other
> is LH thread. The nuts are an 8 sided octagonal nut which no tool that I
> could find would fit, except if you happen to have the factory Churchill
> tool. I almost resorted to having a tool made by a machinist. I did find
> an octagonal socket of the correct size at a heavy industrial tool company
> (for railroad equiupment as I recall), but the cost was $300-400 or more.
> So I resorted to a chisel and hammer and they came right off once I chiseled
> them the correct direction.