Panic, a little more plumbing, but sure, that's even better, if the air cleaner has a port (or port added) for a vent line to the crankcase. There are closed oil filler caps that have a side port for such a line, in mid-60's Chevy's, as I recall. Wouldn't be hard to add a fitting for that to the valve cover as another option, which is what the factory RPO did.
J, shouldn't be any practical difference if the vacuum is at the valve cover, and air inlet elsewhere, or as is typically done on the 216/235/261, vacuum at the original draft tube location and fresh air inlet at the valve cover. The optional factory system had vacuum at a modified draft tube top piece, provided fresh air from the clean side of the air cleaner to a new fitting installed on the side of the valve cover, and used a closed oil fill cap. I like this a bit better than putting a PCV valve directly where the draft tube fit, since it provides additional baffling. See the image:
