It's hard to tell exactly were the oil is coming from.
It appears to seal ok where the gaskets meet the cam towers but there are beads of oil forming at the lower edge of the cam towers which then drip onto the headers see pics.
The engine is a 2.5 short stroke, mag 2.0 litre case, 2.0 litre crank and rods with RS 2.7 pistons and barrels.