I have a question regarding the child safety seat installation in my 1997 F-150 extended cab. The seat base sits up very high in the middle of the rear seat and is very difficult to place the child carrier in. My father-in-law threw out his back the other day lifting and twisting at the same time when taking the baby to the pediatrician. Is it permissible to fold down the rear seat and install the base on the cargo surface?