Ford has had options like this forever and it's usually targeted at farmers and ranchers, I think the first I've found was like a 77 or 78 f250 'rancher' that had a generator option on the main belt off the motor. The ads show a guy cutting boards with a skill saw to mend a fence or something.
edit: I think these also had a ford branded chainsaw over the wheel well on the other side of the engine bay.
Had to look this up, not great pics but very cool:
"The generator was called the Electric Power Pak. From 1969 to 1972, Ford offered a 2,500-watt underhood generator, mostly on the Contractor’s Special, though it could be special ordered on other trucks. It also wasn’t driven off the engine’s belt. It was a separate Onan generator with its own 5.5 hp air-cooled single-cylinder engine, feeding an outlet in the bed. It sat on the driver’s side splash pan. The package the commenter calls a “Rancher” is likely the Farm & Ranch Special, which is one of the trucks that came with it.
The chainsaw was real. Ford sold Ford-blue chainsaws from 1970 to about 1976. They were rebadged Ohlsson & Rice saws: the Eagle I/II and the smaller Hawk. A mount was also sold that held the saw on the F-250’s driver’s side inner fender"
https://www.fordification.com/tech/images/onan_brochure-phot... https://images.squarespace-cdn.com/content/v1/5601f99be4b059... https://www.fordification.com/tech/onan.htm