If you have multiple best men, you have to treat them equally. Same hotel room tier, same swag bag, same say in the bachelor party decisions.
Don’t be the guy who gives Best Man #1 a custom engraved watch and Best Man #2 a “World’s Okayest Best Man” mug. That’s a shit move.
You’re creating a brotherhood for the day. Make sure they all feel like kings. Even if one of them is a little bit more your best friend. They don’t need to know that.