Spelling changes of name after moving to USA

[pnwgal 45]

My fiance will be moving here in a few weeks and I'm wondering about how he can change the spelling of his last name from what it says on his Croatian passport, to a more phonetic representation of his name in English. His last name is (similar to, not exactly) Delačić. On all of the K-1 visa paperwork and the visa itself his name is written "Delacic". After moving here, he'd like for his name to be spelled "Delachich" in the US, because that's how the name is pronounced. At what point can he make that change? Will they let him get a Social Security card with his name spelled differently from what is on his I-94 and visa? Green card?

[TNJ17 1,329]

That’s not how it works. You can’t just change your name like that. In order to do so you must go up in front of a judge and ask permission and fill out a ton of paperwork and give a legitimate reason why you wanna change your name. His legal official name is whatever it says on his visa. That’s what’s gonna be entered into the Homeland system when he lands here. You can’t change that. Social security won’t use a name different from what it says in the system. After getting married you are allowed to go by your married name if your spouse wishes to change their last name to yours. You may use your married name as you please, but in paper (getting a new ss card, driver’s license, etc) that will only happen after you ask USCIS, most likely on your adjustment of status filing, to go by your married name. Once they change that into their system, you may get a new replacement ssc to match your new married name.