The ones on my 950HP are not drilled but it's one that was built by Competition Carburetion so it could be different. The HP and non HP baseplates can be interchanged with those from a double pumper if you need an HP body with a vacuum port for a PCV.
I'm not exactly 100% sure. I would give Bobby a call and ask him but I know that you'll need one that has that channel which runs around the side of the throttles blocked so that the 4 corner idle will function. Give him a call at 775 331-5609.
That should work great for the PCV. I couldn't do that in my situation and I can't remember why but I didn't drill and tap a hole into the manifold either for some reason. I'd say that any similar solution where the stuff that gets sucked into the PCV gets shared equally by the whole engine would work just fine.