For starters look at the shape of your pan, its holes, and compare to the gasket pictures.
If the 4R75W is a beefy 4R70W, though, these two could look the same. A check on rock auto shows the same filter and gasket for both trannies, so should be mox-nix.
Since you have the 351 you should have mostly other heavy duty stuff. I suspect amazon's part finder is not that intelligent and is offering stuff for all F150s, despite that your motor may only be in front of a couple options. Try rockauto and getting part numbers.