Notice the 60 column is hollow and just happens to have an inner diameter that is just slightly larger than the outer diameter of the 40 shaft
here is the gap we need to bridge
And here is a test fit with all the parts in place. the 40 shaft slides into the 60 shaft about two inches
here is the gap we need to bridge
And here is a test fit with all the parts in place. the 40 shaft slides into the 60 shaft about two inches