I'm good with the ole DB protractor. But my favorite was the van den Hul mirrored one with a very fine alignment grid (I can't remember if it's scribed or not.) They used to come only w/ the cartridges, then they weren't available at all. Now they're available as an accessory from van den Hul USA for $20.
http://gallery.bcentral.com/GID5134202DD482363-5-Accessories/1-Phono.aspx
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http://gallery.bcentral.com/GID5134202DD482363-5-Accessories/1-Phono.aspx
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