With that weight a 3/4 ton gas would be fine. Your payload is higher on a gas engine due to the weight savings of the diesel. I think for that weight a 1 ton is way over kill. Most 3/4 ton gas jobs have the payload to handle that. Some diesels may as well if you go that route. The 6.7 seems to be a great engine and if you are looking at the Ford gas the 6.2 Boss engine has been just as good. Truth is most modern gas power plants last a lot longer then years back. They are built to perform the work for a long duration...and yes if the diesel breaks it ain't cheap.......
