Tommyboy -
What I have done with my Webers is to add tall breathers (reworked steel valve covers) and fabricate a Road Draft Tube for one side (connected to an elbow on the other side with 5/8" heater hose). I cut up an old auto tranny fill tube and used it (every body was looking for vintage Road Draft Tubes for Concours cars - the prices are crazy - like $40 for one).
This has worked well for me - a minimum of
oil to wipe off the valve covers, occassionally. The first time I set-up my Webers on my Pantera, I linked two small fuel logs together to gather vacuum from eight ports for the power brakes. I tried to run two breather caps for crankcase ventilation - that was not sufficient - the crankcase pressure built up to the point it would push
oil past the rear main seal (it was a high mileage engine). Adding a road draft tube cured it.
Good luck,
Jeff Burgy