I have a Sheldon 13-inch lathe. The model number stamped in the ways is tmu-18579. there is also a m-7 stamped in the other way. From looking at the pictures on John Knox's website I appears to be a 1955 vintage lathe. I would like to change a service it but need to know what oil to use in the headstock [ISO 68]? Way oil on the rest? I tried e-mailing Mr Knox, but did not get a response. Thanks in advance.