I would think so, but I've never messed with a power steering falcon. You'll have to cut a bracket off the frame of the donor and weld it on the 63. Plus you'll have to swap the drag link and maybe the rest of the steering/suspension components.
You can use the 65 6 cyl power steering parts. But you are better off to use the v8 parts from a mustang v8. Use all 65/66 mustang suspension and steering parts including the spindles. You can not mix them. But you must use the centerlink from the 65 falcon as the one from a mustang is too long. The power ram bracket is bolted on so there's nothing to cut off. You will have to install the two crimp nut inserts for the power ram anchor bracket. It bolts on not welded on.