[mreid]

You can also stick your shop vac in the plenum while you are drilling.

As for the power brake connection to a single runner. It is not an issue for the brakes as once the vacuum signal to the booster is established, it doesn't bleed off until you use the brakes. The pcv is a continual vacuum leak that will lean out the cylinder over time and must be conected to the plenum or carb base.