4 speed tranny swap questions

among finishing the body work and painting the Dart this winter, we are doing an auto to 4 speed swap. I have not done this in over 40 years. kinda scared I may not be able to do it but I have to try. My son wants one in it so I will need help. in looking over some of these posts on here, where do I get a fenderwell ball stud brace. I am sure this car doesn't have one on it. how critical is the placement of it.