Sorry for the long post but....
It is perfectly possible to formulate two identities for the PT from what we hear of Anakin and Vader in the OT and apply them to the footage as it already exists and also augment it with new footage and re-dubbing.
For example consider that in TPM Anakin is not 'a great pilot' when Obi-Wan first meets him (he is an amazing pod racer but destroys the Federation Control Ship by pure accident more than design or piloting skills).
Kenobi does take him on as a pupil but this is because he is asked to by someone else.
He shows no sign of being amazed by his abilities (Qui-Gon does but Obi-Wan is actually rather dismissive and seems as worried as the Council is).
He is amazed by his what's in his blood stream but that not the same thing.
If Obi-Wan in TPM wasn't a pupil of Qui-Gon but was already a fully trained Jedi Knight he could already have a pupil called Anakin (the gifted pilot) but Kenobi finds it impossible to train both so after stubbornly insisting that Qui-Gon's wishes be followed, Vader (Anakin as seen in TPM) is given to another Knight to be trained at some point between Episode One and Two.
Anakin feels guilty about this.
He wants to somehow make it up to the displaced young hero and when he senses Vader's mother in danger but Obi-Wan doesn't seem to take these dreams seriously, he tries and fails to save her.
In her delirium Shmi thinks he is her son who has come to rescue her and the impact of her death as he predicted leaves Anakin psychologically scarred.
Vader is assumed killed in an explosion during the first battle of the Clone Wars but in his nightmares Anakin sees a dark hooded figure taking revenge for Shmi's death and killing Jedi.
Anakin becomes more and more convinced that Vader has turned bad and thrown in with this mysterious Sith Lord that everyone is going on about.
The Separatists have a cyborg General who appears to have a grudge against the Jedi and specifically targets them and the Jedi keep giving the task of confronting him to Obi-Wan.
The only person who listens to Anakin is Palpatine, who drip feeds him his concerns that the Jedi may take advantage of the war and take over for themselves.
He constantly tries to warn the Jedi about his predictions but he isn't trusted because of his connections with Palpatine and because he has broken the Jedi code by marrying Padme (who has become pregnant and also dismisses his nightmares).
Anakin concludes that the General is Darth Vader and his dreams take on a more horrific nature when he see the shadowy figure leading a clone army into the temple and killing children.
Obi-wan is leading an assault on the Separatists on a volcanic planet when Anakin seemingly catches Mace Windu in the act of trying to kill the Chancellor.
Palpatine's warnings of a Jedi take over seem to be confirmed.
He 'rescues' the Chancellor and tracks Obi-wan to the volcanic planet where he has evaded 'arrest' and finds the Separatists waiting for Darth Vader to save them. Kenobi is convinced that Anakin is behind the attack on the temple (an event that really happened just as Anakin predicted).
Vader has 'set up' Anakin to either kill his friend or die by his hand.
Anakin ultimately loses the duel and 'dies'.
In reality Darth Vader did die in the Clone Wars and the shadowy figure in Anakin's dreams, was Anakin all along in a fugue state brought on by guilt and paranoia.
Anakin has died and becomes The Sith Lord Darth Vader only we don't discover this for certain until ROTJ.
Obi-wan takes Padme to Dagobah and she gives birth, she goes to live and die young on Alderaan.
After receiving further training from his unseen former Master (Yoda) Obi-Wan takes Luke to live with Kenobi's brother Owen on Tatooine.
A first time viewer would then have plenty of room to believe Vader betrayed and murdered Luke's father by setting him up for a fall and that the man behind the mask was the same man Anakin was seeing in his dreams (which he was from a certain point of view).
In a way Jake Lloyd even gets to become Darth Vader (just not the same one) and the cyborg General also blurs the line.
Anakin/Vader doesn't stop being manipulated by Palpatine either he believes that the Jedi were attempting to take over and the Empire is the only way to prevent another war.
Leia can remember her mother and we don't find out there were twins until ROTJ.
Obi Wan is trained by Yoda alone and though we hear of him we never see him.
It's not a perfect scenario and it's not the only one but it fits and much of the existing footage could be used to tell it.