Date and authorship

The question of authorship and date are closely related.  Scholars consider this epistle to have been written anywhere between 60-150 CE, with a favorite date between 80-90 CE.  Of course, it all depends on whether you believe that Peter is the actual author.  The date would be between 60 and 68 CE, if you believe that Peter is the author of this letter.  This would be after some of the Pauline letters and before his death in 68 CE.  Any later day assumes that Peter was not the author of this letter, 2 Peter.  How would you be able to date this letter?