Hooking the top one to the tank is wrong but won't hurt anything. It goes from eng to atmosphere, or to the airbox in later models.
The bottom one serves 2 purposes. It is a smaller dia tube and runs to its mat on the lower part of the oil tank. ITs a vent frm the eng to tank. ITs a fefed for the chain oiler from tank to eng.
If it is left to the atmosphere where is the lower tank spigot? Its too small to tightly hold the one from the cam cover.
If it is left to atmosphere it wil puke oil on the swingarm and rr tire.
IF the lower tank spigot is to atmosphere, it too will puke oil.