Susan, welcome to the forum! Actually constructing one of the department store anchors before the mall was fairly common in the late 1960's/early 1970's. Leonard's built both Forum 303 and Northeast Mall stores before the construction for the malls started.
I worked at the Service Merchandise out there from 1989-1992. Toward the end of those years a lot of places really started to shut down. The Service Merchandise did a great business. It was in the old blue Wilson's color scheme then was finally painted gray to match the newer Service Merchandise locations like the one in Irving on 183 at Story Rd. and the one at Hulen. The Forum had a great pizza place in it at the court where the movie theater was. They did a small buffet and when you walked in, sometimes the owner would ask you what you wanted and after finishing your salad I was often pleased to find my choice of pizza on the buffet. They had a big-screen TV in there too, so I recall watching a lot of college football during our lunch hours on saturdays.
When I was in middle school in the late 70's, we used to sneak into the cinema at Forum 303 all the time. The exit door was just inside the mall entrance, so we would hang out just ouside the mall doors and wait for someone to leave the cinema...and we would slip in just as the exit door was closing. And I remember that pizza place well...when we weren't trying to sneak into the Forum 6, we were hangin' in the pizza place! I still have lots of memories of the ice rink as well.