hey doc, have you tried:
http://www.tonearm.co.uk/tonearm_installation_instructions.pdf
or
http://www.tonearm.co.uk/vta-adjuster.htm
or
http://www.tonearm.co.uk/rb300-arm.htm
http://www.tonearm.co.uk/tonearm_installation_instructions.pdf
or
http://www.tonearm.co.uk/vta-adjuster.htm
or
http://www.tonearm.co.uk/rb300-arm.htm