I like the option to be able to drive at 60-70 mph sometimes and worked out that taking it to that speed oil would somehow end up all over the rear tin in the engine bay and over the back of the van. After checking for the usual leaking places, I discovered that the oil was being forced up the dipstick tube due to high rpm/high speed. Replaced the little felt gasket but no change. First off I couldn't believe it was down to crankcase pressure, but on a whim I bought the Empi kit (same as you have), fitted it, vented it into the clean side of the air filter and took it out for a test drive. Result - no more oil escaping/ problem solved - highly recommend if you have the same issue at high rpm.
Ok , how was the breather hose originally connected? ? Stock 20mm ID hose connected to stock tin box or blingy EMPI 5mm ID breather spigot on the shiny EMPI oil filler. Mine used to blow oil like that but it had a knackered engine and an EMPI oil filler so there was nowhere for the blow-by to go to.. These days.. nothing with a stock breather and a basically new engine , running at 65mph..