Registration is not a problem for you. A simple LLC, limited liability company, can be set up in the US. The LLC can legally be owned by you, a non-US citizen, and the Model A can be titled in the name of the LLC. For example, the filing fee in Virginia to create an LLC is $100 and it is quick and easy. The LLC will also give you a US address to use for registration, etc. You will just need a lawyer who is a Model A owner to set it up for you at no charge- I think I know of one!
On the insurance, you may have to check with “regular” insurers such as State Farm, Progressive, and Nationwide as the collector car insurers have more restrictions on use. The collector car insurers are more focused on show cars, limited use, garaged cars, where the insured has other vehicles for everyday transportation.
Best of luck!