Well, to give you an idea - The shortest route from Havana, Florida to Jackson, Wyoming is 2091 miles = 7 days of straight driving at 300 miles/day. Of course how many miles and how many days of stopping enroute can change the 7 days to ??? It depends on you.
Florida US27 to US84 at Bainbridge, GA
US 231 at Dothan, Alabama
I-65 at Montgomery, Alabama
I-24 Nashville
I-57/I-64/I-70 through St. Louis
I-29 Kansas City
US34 at Union, Nebraska
I-80 Lincoln, Nebraska
US191 at Rock Springs, Wyoming
US89 into Jackson, WY and Grand Teton Nat'l Park