Guide: Stamp 63 - Solved the ghost mystery!

How to get Stamp 63

First visit the large building with a bell on it in the north part of White Mountain, and hear the ghost story.
Then Warp to White Mountain.
From the Q's Factory, go left but instead of going up the mountain path, turn left a little and enter a cave with a NEXT CITY sign next to it.
Follow the path until you enter a large opening in the cave.
Drive right into the ocean and you'll find some ruins.
Search around the ruins for a black bus, and talk to him.
Then return to the building with the bell.