The tower, the sole structure on the block that remained from the early 20th century, was renovated starting in 1961 to harmonize the design with Morgan and Meroni's east wing. Starrett Brothers & Eken were the general contractors and Purdy and Henderson were the structural engineers. During this time, the clock, bells, and roof were rebuilt. The renovation also remodeled the facade so it would be stylistically similar to the east wing, and so the decaying marble was replaced with limestone. Morgan eliminated most of the ornamentation added by LeBrun, though he preserved the clock tower's general proportions, and designed the east wing so that the tower would rise behind setbacks on the 10th, 11th, and 13th floors. The project was completed in 1964.