Change from Manual to power 67 Dart

Hi i have a 67 Dart with a 383 mounted in a 6 k frame now manual box. Want to change to power box off a 68 to 76 A body to my 67. Have always been told 67 had a diffrent spline or pitman arm was diffrent. What kind of issues will i get into changeing the power box off a 1970 A body ??