I ordered a couple hundred tapered plastic bushings YEARS ago from Athern , they were used on their H O dummy engines . They used a brass like bushing in the powered units. I pointed the axles by placing them in a lathe & filing the axles to a point . The big problem was to shorten the axle a little ( guess work ) to have some end clearance . The roll ability is great & will do some more cars if I live long enough . I did several of the cast drop center cars & added custom loads.