This story is a sequel to His Book of Gears

When Justin's average Ponyville day is interrupted by Celestia with a special request for him, his week gets a little more interesting. Tasked with reforming the former Queen Chrysalis of the changelings, he might have his hands full. Will she finally accept friendship into her heart and live the pony way with Justin, or will her conflicted feelings on the matter cause her to revert?