Bingowings said:
Perhaps the motion of a TIE-fighter could cover the wipe (nothing says OT to me more than a TIE) :

I really like this idea. Coupled with the imperial march chiming in at the right moment, this would give me goosebumps!
Bingowings said:
My idea was to have Grievous do the falling down thing so popular with Star Wars characters (he has already done the hand cut off thing).
Which would possibly mean making a model with the new head and filming it tumbling to an uncertain end.
If all direct references to Anakin being Vader until the end, were removed it would leave a question mark over which one is Vader.
You could even redub his lines so Grievous says something about learning from every fight he has had with Obi-Wan so he is a pupil of his 'from a certain point of view'.
Grievous has spent a lot of time hunting down and destroying Jedi.
Haven't figured out how Obi-Wan can get away with the betraying and murdering line yet though.
I think the line "who was a pupil of mine before he turned to evil" is the most problematic thing to try to account for. If this line didn't exist, we could just assume that Obi Wan is protecting Luke from both the fact that his father turned to the darkside and covering up for having brutally killed him himself.
This is why I've previously proposed a more radical edit of not having Hayden Christensen (or Jake Lloyd) be Anakin at all. That way, we initially assume that Hayden became Vader, and survived his ordeal on Mustafar, and then went on to hunt down the remaining Jedi - one of which would have been Luke's dad. (which accounts for the betrayed and murdered your father line)
Until, that is, it's revealed in ESB that he is in fact Luke's father, and "Hayden", we can assume, died from his injuries (YAY!)
As for actually seeing Anakin in the prequels. Adywan has demonstrated what can be done with the emperor's hologram in ESB:R. We could have Anakin communicating with Obi Wan, or others via hologram, and some wizardry like on the ESB:R Emperor hologram could bring a young Sebastian Shaw to life. Get someone with a similar voice and accent as ROTJ Sebastian Shaw (not that critical seeing as he's got no lungs by that point), and hey presto! Some dialogue between them could also account for the "was once a pupil of mine" line too. Obi Wan, now equal with "Hayden", had begun training a new Apprentice before the events of Episode 3. We could even, at one point, after Hayden "dies", have Sebastian Shaw-Anakin get attacked by an anonymous figure, have the hologram cut out, leading us to think Hayden survived (which would be reinforced by the end montage where we see armoured vader overseeing the death star's construction), and that Shaw-Anakin is now dead, but leaving enough ambiguity so that we can make sense of it come the revelation in ESB. Phew! I'm confusing myself now.
Not sure what scenes or dialogue we have to work with for that, however. One could have the Sebastian Shaw impersonator doing most of the talking if our ObiWan lines are limited. Anyone interested in doing a mockup of a hologram of a young Sebastian Shaw, just to see what it would look like?
Not pretending this isn't a very radical and difficult (probably impossible) edit to pull off, but it's the absolute only way I can think of to account for the prequels ruining the impact of Empire. This would then cease to be Anakin's story, but Obi Wan's in the PT, who then passes the torch to Luke in the OT to carry on the hero's journey.
EDIT: Here's an example of a young Sebastian Shaw as a Jedi. Sorry I couldn't find a bigger size.
