ok so getting damaged studs out of rear of ba , simple, but................... how the hell do u put new ones in

Use a high tensile (grade 8) 1/2" UNF nut, and a few washers, maybe 6 of them, put some grease inbetween the washers ( these greased up washers act like a bearing), align the splines as best as you can before you apply torque to the nut......thats how I have done them before.