I'm going to post the relevant verses from Mark and John, and highlight the ones that I'm specifically referencing, so you can tell me exactly what I'm getting wrong:
From
Mark 14:
The Last Supper
12 On the first day of the Festival of Unleavened Bread, when it was customary to sacrifice the Passover lamb, Jesus’ disciples asked him, “Where do you want us to go and make preparations for you to eat the Passover?”
13 So he sent two of his disciples, telling them, “Go into the city, and a man carrying a jar of water will meet you. Follow him. 14 Say to the owner of the house he enters, ‘The Teacher asks: Where is my guest room, where I may eat the Passover with my disciples?’ 15 He will show you a large room upstairs, furnished and ready. Make preparations for us there.”
16 The disciples left, went into the city and found things just as Jesus had told them. So they prepared the Passover.
From Mark 15: This took place after they ate the Passover meal, since Passover began the night before:
The Crucifixion of Jesus
15:22–32pp—Mt 27:33–44; Lk 23:33–43; Jn 19:17–24
21 A certain man from Cyrene,o Simon, the father of Alexander and Rufus,p was passing by on his way in from the country, and they forced him to carry the cross.q 22 They brought Jesus to the place called Golgotha (which means “the place of the skull”). 23 Then they offered him wine mixed with myrrh,r but he did not take it. 24 And they crucified him. Dividing up his clothes, they cast lotss to see what each would get.
25 It was nine in the morning when they crucified him. 26 The written notice of the charge against him read: the king of the jews.
The same account from John, where there is
no mention of the Disciples asking Jesus where to prepare the Passover meal. There is also no mention of Jesus doing the "This is my body....." speech.
John 13:
Jesus Washes His Disciples’ Feet
13
It was just before the Passover Festival. Jesus knew that the hour had come for him to leave this world and go to the Father. Having loved his own who were in the world, he loved them to the end.
2
The evening meal was in progress, and the devil had already prompted Judas, the son of Simon Iscariot, to betray Jesus. 3 Jesus knew that the Father had put all things under his power, and that he had come from God and was returning to God; 4 so he got up from the meal, took off his outer clothing, and wrapped a towel around his waist. 5 After that, he poured water into a basin and began to wash his disciples’ feet, drying them with the towel that was wrapped around him.
John 19:
13 When Pilate heard this, he brought Jesus out and sat down on the judge’s seat at a place known as the Stone Pavement (which in Aramaic is Gabbatha). 1
4 It was the day of Preparation of the Passover; it was about noon.
“Here is your king,” Pilate said to the Jews.
So, again, John specifically says that he was already arrested by noon on the day of Preparation of the Passover. Mark specifically says Jesus gave instructions for the Passover meal (the day of Preparation), ate the Passover meal with his disciples and was then arrested and crucified at 9am on Passover. What am I manipulating or making up?