I didn't think about Fort Knox until reading the other replies, but I can see how that would become a joke if you were calling your kids' names at a playground or similar.
The names seem strongly American to me-- like "heartland" American. With Ford, I instantly think of the car manufacturer and then the former president. I don't have any mental association for Knox. Just seems like a trendy name ending in "x" (see Dax, Jax, Maddox) Not my style but I think they might work better for middle names.
I really like the name Ford it's manly and different.
Knox is ok.
I like Ford. I think of someone masculine and handsome with this name. I prefer it to Knox. But I wouldn't worry too much about the Fort Knox thing, it's not a fn/mn combo, it's brothers.
Many of your name combos seem to be teetering on the line of handsome and action hero to me though. Personally I would just try not to get too far past that line. Otherwise, go for it.
Well despite the negative feedback on Knox- I for sure will be using it because, as annoyed as I was to have it go "celebrity," it is my maiden name that used to be obscure and I have always planned on using it on a boy. And my dad would be too disappointed if I let its untimely popularity sway me. Ford my be just a passing fancy but right now it seems so handsome and perfectly uncommon to me. Hubby may be the deciding "no" on it, but most of the time that thought just makes me like the name even more bc I feel I cant have it. Haha!