[Neweller]

Both Action and Bennett are good choices. I have used Bennett and Deer Creek. It's always easier and less to use someone in Helena since that is where the secretary of state is. The registration will be in the LLC name. You can physically live and have a license anywhere in the country it doesn't matter.

Here is Bennett's website: Montana LLC

Here is Deer Creek website: Montana RV Registration | MT Registered Agents | Tax-Free Montana LLC : Deer Creek Corporate Services

Here is another for reference: My Montana LLC vehicle registration