TheSmartGuy's Guide on Making Mesos

I didn't see if it was said but I'd scratch off Missing Mechanical Parts from the quest list (unless they fixed it during the CwK patch), it's glitched. I've done it twice over the summer and both times, I got no reward, no EXP, was not removed from the quest map, and did not have the parts removed from my inventory, the quest merely went into my "completed" list. I also know it's not cause I chose the "wrong option" when talking to the Cheng in the quest room because between the two characters, I have chosen both options. So now I am reluctant to do the quest again with my new page until it is confirmed that it is fixed, I don't want to miss out on a third scroll.

tl;dr: Missing Mechanical Parts quest is glitched, don't do it.