@Blujely – about your initial question about showing a specific character at an n-th position in a story, you could use a simple GREP search in InDesign and restrict that search to a specific story (e.g. the story of a selected piece of text):
Search for the n-th position with the formular in dummy-syntax:
Positive look behind of any character in the exact length n-1 + character
E.g. if you want to look for a "carriage return", defined in GREP as \n at every 10th position, search for:
(?<=.{9})\n
In your case that would be:
(?<=.{8000})\n
Uwe