The problem with "scrip[ture build up" as a hermeneutical approach is that it assumes the reader will have the multiple scriptures to build on each other. The writers of the gospels assume no such thing.
Without reverting to my presupposition, I need to challenge the believers' (assumed) presupposition that the authors of the Bible are aware that they are writing scripture, or that God is behind it all. The writer of Mark had no idea others would come after him. The writers of Matthew and Luke thought they were improving Mark, once and for all. No origin story? Let's fix that with two utterly incompatible accounts. No resurrection appearances? Let's fix THAT with more utterly incompatible accounts. None of the gospel writers assume the existence of the others or access to the others. Each seemed to think their gospel was the only one you needed to get the point. That makes the argument for scripture build-up almost entirely supernatural. That is, the writers didn't know this tactic would be used later, even if the Author did.
I mean, FINE if you want to believe that. But it strains credulity, even assuming divine inspiration.
Why not have all four gospel writers make it clear there were four others crucified? Why not have AT LEAST ONE do so?
Why not have Matthew make it clear Judas was still alive through the resurrection? Why force us to read angst into a passage that's clearly about suicide by hanging?
Why have one writer clearly say Jesus appeared to The Eleven (not 11 of the 12) and then have ANOTHER one imply Thomas, not Judas, was the missing disciple? John never says Jesus appeared to 10 of the 11, with Thomas missing. Luke (or was it Matthew?) never says Jesus appeared to "the 11" but one was missing, but I'm going to leave it to someone else to tell you who it was.
It's true that different blind men can have wildly different descriptions of an elephant. But that's hardly an argument for omnisciently divine authorship of the documents we're reading.
Assuming any historical value to the narrative, the story is abundantly clear there were three crosses on that hill.
For what my heathen opinion is worth.
I am confident George is right. I will add one of my favorites: Chester Alan Arthur.