Overhang is set separately, and is set before aligning the cartridge. Once the overhang is set correctly (so that the stylus will track the curve on the protractor) then you set the alignment. Overhang is also much easier to set. It's always been alignment that I've struggled with (perhaps I should buy a cartridge with a conical stylus :-)
I was expecting someone to mention that the cantilever is not always parallel to the cartridge body. This is absolutely true, and correct alignment really requires sighting down the cantilever from the front of the cartridge. However I'll admit I find this extremely difficult to do, so the trick of using a sewing needle to align the cartridge body is probably as good an alignment as I'll ever achieve.
I was expecting someone to mention that the cantilever is not always parallel to the cartridge body. This is absolutely true, and correct alignment really requires sighting down the cantilever from the front of the cartridge. However I'll admit I find this extremely difficult to do, so the trick of using a sewing needle to align the cartridge body is probably as good an alignment as I'll ever achieve.