Yeah, you’re going to need some metric hex wrenches. You’ll need a 1.27mm for the timing pulley, and I think a 2.5mm for the stepper motor bolts. You can find a small/inexpensive set containing the sizes you’ll need.
Loosen one of the screws holding the X axis belt to the carriage to relieve tension on the pulley.
Reference Step 6:
At this point, you will be able to tell if the timing gear is loose or if the stepper is broken. The shaft fell right off on mine one I had removed the belt.
I don’t think so. If you need one, get this one from Lulzbot:
The two stepper bolts next to the frame were a bit of a pain to access, but it’s a fairly straightforward and easy job to replace the stepper if necessary.