Where do the writings of John place chronologically according to preterists? Under the preterist view that all of John’s writings we're completed prior to the fall of Jerusalem in 70 AD, where would they be placed chronologically in the New Testament canon?
You will find exactly what you are looking for in Ed Stevens's paper "Introduction to the New Testament Canon" - for the Preterist Bible Project, written April 2011.  He covers the "why" of the Preterists position as opposed to the theory of canon formation held by Roman Catholic as well as some Protestants, even evangelical theologians who all hold creeds like the Nicene and the Apostle's creed as legitimate and authoritative.  But the Preterists only believe the apostles of the first century to be authoritative (and thus became the basis of the NT canon), and the later generations merely recognize the already established books in the canon.  

Secondly, the Preterists also believe all NT books to have been written before the destruction of the temple in Jerusalem in AD 70, including all of Apostle's John's writings.  The paper I referenced above includes one dating scheme of all NT books.  Because most Christian scholars have dated the book of Revelation to mid AD 90, Preterists became well known for their extremely early dating of Revelation, which heavily affects their interpretation of the prophecies within the book of Revelation.  See this short 1985 book by Arthur Ogden "An Introduction to the Book of Revelation" as an example of how Preterists defend the pre-AD 70 dating of Revelation including extensive argument and historical background to support it.

Here's Ed Steven's dating scheme of all NT books:


  
  1 Thessalonians (AD 52)
  2 Thessalonians (AD 52)
  Galatians (AD 52-53)
  1 Corinthians (AD 57)
  2 Corinthians (AD 57)
  Romans (AD 58)
  Matthew (pre-AD 58)
  Mark (pre-AD 58)
  Luke (AD 58-61)
  Acts (AD 58-61)
  John (AD 60-62)
  1, 2, 3 John (AD 61-62)
  James (AD 62)
  Revelation (AD 62-63)
  Ephesians (AD 63)
  Colossians (AD 63)
  Philemon (AD 63)
  Philippians (AD 63)
  Hebrews (AD 63)
  1 Timothy (AD 63)
  Titus (AD 63)
  1 Peter (AD 63-64)
  2 Timothy (AD 64)
  Jude (AD 64-65)
  2 Peter (AD 64-65)