I would first suggest that you find out if your Mexican insurance provider will extend coverage to your vehicle so you can drive from Mexico to Florida. Many Mexican car insurers appear to have what is called border insurance for trips into the US from Mexico.

In order to operate your vehicle in US, you must abide by the various state laws of the States in which you pass through. Typically each state will require you to have a current Mexican driver's license, current Mexican license plates, and current vehicle registration. If the vehicle is not registered in your name, you should carry a letter from the owner authorizing you to use it.

Mexican citizens, who already have a visa and are planning to travel to the United States beyond the border area and/or for longer than 30 days, must obtain an I-94 permit at the port-of-entry from a Customs and Border Protection officer.

The permit may be issued for a maximum term of 6 months and for multiple trips to the U.S. The issuing Customs and Border Protection officer will determine the exact conditions of the permit. The I-94 permit must be returned to a border port-of-entry upon or before its termination and the visitor's return to Mexico.

Check with the US Customs and Border Patrol, www.cbp.gov, for complete information about entering the United States and I-94 permits especially since you will be staying in the United States for over 6 months.

A valid Mexican driver's license may allow you to drive within the United States (though you would need to check with each state's DMV since laws can differ) but typically insurance companies within the US will require you to obtain a valid license from a State within a short period of time of starting up an auto insurance policy.

Florida requires any part-time or even seasonal resident living in FL for 90 days or more during the year to obtain a Florida personal injury (PIP) and property damage liability (PDL) auto insurance on their motor vehicle. It can be difficult to obtain insurance without having a US state driver's license. The Florida of Highway Safety and Motor Services gives information on how a non-United States citizen can obtain a Florida license.

If you have Mexican insurance covering your vehicle in the US until you obtain your Florida car insurance it would not appear that you would be breaking any laws. You should check with the FL HSMV though to make certain what the state of Florida requires from you to legally drive your vehicle in Miami and throughout the state.