Instructions
Find the mailbox with a face on it. There are only a few mailboxes around the neighborhood, and only one is animated.
Wait for the mailbox to stay still, and then jump on it. Steady the controls, and wait for the mailbox to start jumping in the air.
Double-jump when the mailbox is at the highest point of jumping. Reach the far ledge.
Walk along the edge and stay to the side, so you do not fall off.
Reach the end of the ledge, and a cut scene will play. Mickey will climb to the safe, use his thinner and release the safe without hurting Moody. Once the cut scene ends, you can complete the level.