bulhead

Very new to the site, not sure if i am doing this right but here it goes. Anyone familar with 1983 vriago forks? I have a 920, near the top of the forks the is a bracket there that has an airvalve on the side of the fork on the clutch side, not where it should be, on top of the forks. there is a hose the runs under the neck to the other fork. I am sure it has to do with equalizing air in either fork. However the manuel is not showing this type of fork set up. does anyone know if this was stock. or am i looking at some ones modifications. and if so... I should be able to replace those forks with most any 36 mm forks....Right? Please help. thenks bulhead