Oh man please get the best stereo microscope you can afford if your going to work on them and you can thank me later, Some of the adjustments that need to be made require that you can see exactly what you are doing and what is the out come of any adjustment is that you've made. Like the indexing finger for example when you push the fork tine from it's resting point towards center you need to be able to see how many teeth on the indexing wheel the indexing finger ratchets a crossed, Is it 3, is it 5, is it 9, you need to be able to clearly see that and a hand full of other adjustments as well....