Car seat question.

So we are making a huge road trip from middle Georgia to Las Vegas. My son will be 2 in February and he is a big boy. He is almost 3tf tall and is 32 lbs. I want him to be comfortable while we drive. But I also want him to be as safe as possible. His legs are bent and he hates the car seat, mainly because he is uncomfortable. Advice about forward facing him for the trip? By the standards of the car seat he meets the requirements for forward facing, in just nervous. Thanks you in advance.