I'm a bit confused, partly as I am working from a series I manual.
there is an oil line which attaches to the rocker box with a banjo
fitting and feeds the 2 rockers, that seems OK. Also there is an aprox
3/16 tube inside the rocker box (push rod side of the inlet rocker)
pointing at the rocker cover, this is where the jet of oil is coming
from. I had thought it was a crank breather tube but......maybe it
should be!

Matt