1930 throw-out bearing

Have you tried the H-E-T Club's manuals online (courtesy of Alex Burr)? I see a 1930 Essex parts book there, with a drawing of the clutch and components. The part number is given, and if you go to the 1930-39 parts interchange you can determine if the Essex clutch components are the same as used in the 1930 Hudsons. (Someone wiser than me will know this, and can post the answer here). Anyway, the principles are probably the same if not the actual parts.

You'll find a list of Hudson literature online at http://hetclub.org/burr/lithomepage.htm