I have a 1977 F-150 that i want to wrist an arm on. I have a parts 79 bronco and i want to know if the arm from the bronco will work on the f-150. I thought there was something different between the way they mount. All help is appreciated.

PS I searched.

Yep, same arm. Go for it ;)

The bolt spacing for the coil bucket is different between the 77's and the 78'+ R/As. That's the only difference I know of. Bronco's and F-150s used the same stuff.