I just found a website which answered all my questions regarding wiring changes to update the glowplug controller and relay on my 6.9.Wiring diagrams as well as text. There is info here which goes clear back to the early '83 contoller. Lots of other great info here as well.
http://www.intellidog.com/dieselmann/idi2.htm
http://www.intellidog.com/dieselmann/idi2.htm