Installing a replacement clamp is Ok for a 'McGyver' fix, that is get it going now and/or a student that doesn't have much money.
A proper fix is to obtain a complete cable from Ford.
Once the cables/clamps are on the battery then tug hard the battery clamps sideways, they must not move, if they do move, then perhaps the clamps are not seated all the way down on the post because of some anti-corrosion felt washer. Perhaps in the case of old/worn clamps then placing some metal pie plate aluminum between the bottom of the clamp and the 'anchor' end of the bolt will work. IF that works, then hunt around some hardware store or craft shop for a thin piece of brass to replace that pie plate material to avoid galvanic corrosion due to dissimilar metals