If you e-mail me I may be able to help. Neil Shuttleworth has written a book (with Ron Hill) called Manchester Marathons, which included Stockport maras. Whilst it does not have full results I probably have Neil's address, or that of a guy called Hamish Thomson who is both a Stockport Harrier and a contributor to the book.
Incidentally, I doubt if you ran the frst three Manchester marathons: the first was in 1908! In the "modern" era there was the maxol series in the early 70s, followed by the 80s revival, with the 1981 to 1985 series, often known as the Picadilly marathon.
Standards were high: Steve kenyon ran 2:11, and 2:40 did not always guarantee a place in the top 100.
The Stockport(or Daffodil) Marathon was a much tougher proposition, both because of the course, and early April weather.