The guys I knew who did it mostly used the Grafmatic 6 shot backs so all focusing was done with the Kalart rangefinder.
Focusing on the ground glass was just not happening in the press environment.
Thus they used the one lens that was on the camera as lens swapping would have meant recalibrating the rangefinder - not something you're likely to do in the field on a moments notice.
Other than the camera and a couple or three grafmatics, the flash gun and a pocket full of Press 25 or #5 flash blubs was the essential kit. If you look at the press work from the period you'll see many many images made with the direct bulb flash, even outdoors, because of the maximum lens apertures and film speeds.
The phrase "F8 and be there." to describe press photography's most important duties came from this period.
Toward the end of the Speed Graphic era in the 70s I saw some rigs outfitted with the Honeywell/Singer Strobonar electronic flashes but by that time most guys were moving on to the new 35mm systems as fast as they could.
The Associated Press and Time Life have published several "best of" photography books that give the camera specifics for each image. Flipping through one of those will give you an idea of how the press camera/twin lens/35mm eras overlapped. The mighty Speeds lasted farther into the late 20th century than most folks imagine.