Hi TU
That's a novel method of setting the crank endfloat? I hope that bolt is rigid enough?
It looks like the crankcase has been drilled and a second breather pipe added
I don't like that idea
The standard timed timed breather works well once attention is paid to the cork washer thickness on the rotating
"top hat"
An open breather will just add to the pumping losses of the engine as I'm sure you know
Fitting a Bunn breather is the other option ?? (if you can find one)
John