What size engine is the Ford inline 6?

A buddy of mine called and said his uncle had a F150 with a good motor but a trashed and it was rear ended. I've been looking for a engine for a swap into my Bronco II but all the info he has on the engine is it is a Ford Inline 6. I've done the google search and it says that it is most likely a Ford 300 4.9. Did Ford make any other inline 6 engines?