They finished 2nd and 3rd in the Isthmian prem, which is equivalent to where they are now around 83-85.Correct me if I'm wrong, but haven't the last couple of seasons been their highest ever finishes in the league by some margin?
They are also likely to break their all time record attendance next season.
Their peers at the time were Sutton and Wycombe, the latter who then went up and made it into the league within a few seasons (I think).
Edit - the Isthmian winners, Southern league winners and Northern league would then go into what is now the national league.