Tim I think you need to ask yourself questions like
Can I make it with out AC through the plains and deserts?
Is the car small that would make my 7' 6" stature cramped?
Can the car handle the heat?
Will I either hate the car by the time I get there or love it?
I went cross country in a 1984 Ford Ranger. I loved that truck but sold it as soon as I got back to but a bigger truck.