I aligned my mirrors and the K40 is still engraving unevenly. The lines get faint the further away from the home spot that it gets. Why O wise Gurus?
Please post photos demonstrating the problem and describe anything you have done to debug so far.
Are any of your mirrors in backwards by any chance?
If you haven’t yet found https://donsthings.blogspot.com/2016/11/the-k40-total-conversion.html you want to visit, and then thank @donkjr for putting together lots of useful information. 
The mirrors are in properly. Two haven’t been taken out yet. The one was taken out to add air assist and the gold one was put in with the bevel side up. I’d send a pic if I could figure it out as far as how to.
Please run through the site tutorial that you were offered when you signed up. It shows up to upload an image. Thanks!
Check and make sure your bed / work piece is level / parallel relative to the x-rail.