DF Shadow said:

I think the "your mother once thought as you do" change would be an appropriate edit. At that point in the saga everything is coming full circle and Luke brings up his mother anyway earlier with Leia.

The line is in reference to there still being good in Vader - which are Padme's dying words.

I just don't know if it could be done well enough. There has to be a JEJ movie where he says "mother" that can be worked with.....that's where we need to start.

I dont have it on me, but perhaps during his last monolog in 'Conan The Barbarian?'