The grandiosity of “The Gilded Age” wasn’t just about clothes and servants. To scale the show, the production team had to go big. Set in 1880s New York City, the team on the HBO series that premiered Monday were tasked with recreating a world that barely exists today. Heiress Caroline Astor’s home was demolished and made way for the Empire State Building. An office building sits in the plot once owned by horsebreeder William K. Vanderbilt. The Bostwick Mansion, built by a founding partner of Standard Oil, is now a luxury apartment building. So directors Michael Engler and Salli Richardson-Whit…