Have you noticed that the pipe only pukes oil after longer rides, but not after shorter rides aroud town? If so, this happened to me and we initially thought it was the guide but it turned out to be a poor return of oil/pressure issue. Pressure kept building up in front head and needed a place to go. Eventually after longer rides it would blow some out the front pipe. Wouldnt notice it around town as the short trips allowed the oil to slowly drain down.
Not familiar with the Branch Head design. Maybe someone familiar with Branch Heads can chime in.