I ran across more evidence in favor of "Good Friday is actually Good Thursday" - (see http://uvulapie.blogspot.com/2008/03/thank-god-its-good-friday.html)
Why do I harp on this so much? Because I'm a stickler for truth. If God's Word says something then we must align ourselves and change in response to this. I personally don't care if a thousand years of tradition say otherwise, if recently (in the past hundred years) uncovered manuscripts illuminate Scripture to provide greater clarity or rectify an incorrect, though for some reason dearly held, position then it's time for a change. I mean, if people can't admit and adapt to something as well documented inconsequential as Good Friday/Thursday because of their traditions what of bigger, more important changes that God may want to correct in our lives?
So there I was, perusing The Gospel of Peter and... what? Yes, since I read a book on the early Church fathers I've been interested in their early writings. No, I don't hold them to be on par with Scripture but they do provide a glimpse of early theology that has not be tainted. For instance, if someone believed something incorrectly you could just go ask one of the apostles directly for clarification.
But in this case, The Gospel of Peter is a very brief telling of Christ's crucifixtion, death and resurrection. What did I find in support of Christ being crucified on a Thursday?
 But of the Jews none washed his hands, neither Herod nor one of his judges. And since they did not desire to wash, Pilate stood up.  And then Herod the king orders the Lord to be taken away, having said to them, 'What I ordered you to do, do.'
 But Joseph, the friend of Pilate and of the Lord, had been standing there; and knowing they were about to crucify him, he came before Pilate and requested the body of the Lord for burial.  And Pilate, having sent to Herod, requested his body.  And Herod said: 'Brother Pilate, even if no one had requested him, we would have buried him, since indeed Sabbath is dawning. For in the Law it has been written: The sun is not to set on one put to death.'
And he gave him over to the people before the first day of their feast of the Unleavened Bread.
That would be the "special Sabbath" mentioned in John, the Sabbath on a Friday that occured before the usual Sabbath on Saturday.
I'm just sayin'.
Read the entire text yourself here.