63 Dodge Dart, now let me see;)

Nope, Couple hits with a mallet and a block of 2x4. Don't be bashful.
I used the same 74-76 A body disc brake components on both of my 63 Valiant and the 64 Dart.
The more you do the more you will see tolerances being + or - No two Mopars are exactly the same.
Yes the upper ball joint from the 63 has a smaller taper stud.
You must use the 76 Upper control arm and ball joint (Yes they do make adapter sleeves and yes they work)But you have the correct parts.