Before it was Lockheed Martin, it was General Dynamics.
The GD plant in Fort Worth for decades built military aircraft and in this photo from 1986, workers are completing a F-16. The plant was sold to Lockheed Martin in 1993 and is currently manufacturing the F-35.
The caption with this photo said, “Final assembly area at General Dynamics is a ‘beehive.’ Workers surround a nearly-completed F-16 Thursday morning. The aircraft will roll by the end of the following week.”