So I've created this cool temple prop, but when I drop it onto a scene or zero out its coordinates, it's way off from the center of the scene. And Control-D drops it a bit below ground level as well.

Can someone tell me how to redefine the origin such that it defaults to the center of ground for X and Z, and sitting on the ground properly for Y? I'm guessing it's simple -- if only I could figure it out!