Gimbels Paramus, which comprised the Stage III mall construction project, encompassed 245,000 square feet. By Macy's decree, it had to be smaller than Bamberger's. The opening of a Gimbels store, at GSP, signaled a truce between the Macy's and Gimbels chains, who were arch retail rivals (Note: Macy's owned and operated the Bamberger's chain).
Photo from www.dshistory.com

Graphic from Gimbels Brothers, Incorporated

A circa-'60 plan of New Jersey's mammoth merchandising mecca. The Stage I mall appears in black. Its Stage II expansion, opened in the fall of 1958, appears in dark gray. The complex was completed with Stage III (in light gray), which was dedicated in August 1960. GARDEN STATE PLAZA now extended for 1.3 million leasable square feet and contained seventy-two stores and services.

In 1975, the "world's most exciting shopping center" is still open-air. A multi-phase renovation would soon get underway and not be completed until 1984.
Graphic from R.H. Macy & Company

The Food Court, a 14-bay culinary complex, opened in October 1982. It was built in Level 1 (or basement) space. Eateries included Bon Croissant, South Philly, Small Frys, Zapata's, Flip's and Scoops ice cream.
Graphic from R.H. Macy & Company

Courts and concourses at GSP were enclosed and climate-controlled between 1981 and 1984 (these modifications shown in light gray). In 1988 and 1989, the basement floor was retrofitted as an additional level of retail. "Level 2" depicted here was the original Mall Level of the complex. With these improvements, the complex covered approximately 1.6 million leasable square feet.