heres my old set up , never dropped any oil even under heavy loads.

bailey oil seperator / breather



top -10 fitting (small) to rear cam cover
top -12 x 2 fittings go to x 2 fitting machined in to rear of the engine block
bottom -10 fitting to rear of sump
bottom -10 fitting to vent or fitted to a catch tank( i never needed one)



x2 breather ports on rear of the engine block , ive seen people use 1 , ive seen people plumb back into the front breather port ,theres many different ways and iam talking from my experience and this is imo the best way to breathe the engine.

hope this helps

cheers paul