Get a 100x loop. Make sure you have lots of light from outside, and if you can perform the task outside. They are accurate, but you meed good eyes, and again, lots of light. Take your time, and you'll get it right. Good luck.
cartridge alignment
When I look through the illuminated magnifying glass provided by mintlp if I do not have the magnifying glass set up correctly, it can appear as if the cantilever is aligned but it is not due to distortion from the lense of the magnifying glass not being in the correct position with respect to the cantilever. How do others make sure they they have their magnifying glass set perfectly while aligning their cartridges?