On Sunday, the Los Angeles County Museum of Art will finally open its latest "destination artwork," Levitated Mass. That's the name bestowed on the 340-ton boulder transported from a quarry in Riverside through four counties and 22 cities on a 300-foot-long vehicle designed for the purpose. Michael Heizer is the artist who thought it up, but it was Michael Govan who had the vision and persistence to bring it to LACMA.