1963 289 2bbl. Intake manifold has the crankcase vent that comes up on back of intake man. and goes thru tube to carb spacer intake port. Valve covers have no oil fill holes or breather caps, just the oil fill tube on front of motor. I'm changing to edelbrock 4bbl intake that has no milled opening on the rear for the recirculation of the cranckcase blowby. What mods should be done? Thanks for help Tom G