Need help and info to help out my autistic son with his project

Autistic kid building a 66 cuda with a 440 my son needs help and has been told this can't be done and that we can't even get headers for it the motor is almost complete and it's a monster and he built it himself it's beautiful and will make lots of power but the issue is now getting it in that car everyone says it's no way I want to see my son's dream come true the car is in rough shape but he bought it and now wants to follow his dream