Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
The early tanks vent to air from the top generally, they have a built in air oil separator inside the tank that splits oil vapour to drip back into oil supply, with air going out to ground. This is from description in KO manual, you'd have to look at later manuals to see your K model. They have to vent both tank and crankcase, ultimately to atmosphere, to prevent overpressure in engine. Sealed completely, it'll try to push oil out of oil seals etc. Also interferes with dry sump system on 750 as you don't need either vacuum or pressure exerting against oil pump operation.
looking great Mick fancy having a crack at mine when your done?