Back in 88 I had to rebuild that joint on my 64 300, the housing was scored up. We got it out but I will be danged if I remember anything difficult about it. Of course I was in the service and we had retired machinist's working at the hobby shop who grew up with these cars and knew the tricks.

Got my stuff from Andy Bernbaum, https://www.oldmoparts.com/parts-universal-joint.aspx, kit Q-103 (I think) is the one. Not sure if they are NOS, might want to ask.

They say there are no such thing as a stupid question.
They say there is always the exception that proves the rule.
Don't be the exception.