Don't drill them out......
Crankcase pressure is caused by piston blowby
Drilling the larger holes in "dirty side" PCV orifice on your V6
Will lower crankcase pressure a little bit
Drilling the larger holes in orifice , will REDUCE the "crankcase gunk that backs up your cleanside PCV breather hose which will reduce oil in your air intake plenum (just beyond your air filter and before throttle body)
... Drilling larger holes will reduce, but not eliminate crankcase pressure, such as during wide open throttle
or if you have really worn piston rings
In those cases crankcase pressure will still push crankcase gunk up through you cleanside PCV hose in order to relieve crankcase pressure
Drilling larger dirty side PCV holes
Will give you will get more intake valve carbon build up ( the enemy of every gdi engine)
And you will get more oil in intake manifold ( beyond the throttle body)
because more crankcase gunk will flow thru the bigger holes in the dirty side PCV ....
(If you drill holes you might need to install the new redesigned valve cover gasket that also has splash shield to protect the larger holes from oil splash ?)
(unless you have a catch can to catch the gunk that flows thru the larger holes !)
I would get the $80 vented oil cap,
Which keeps crankcase at a nice zero (or negative) psi pressure.
At zero PSI crankcase pressure no crankcase gunk will ever be pushed up your cleanside PCV hose and when crankcase is at negative pressure (vacuum) clean air will flow from your air intake plenum, via clean side PCV hose, into crankcase as it should.
In fact.... with the vented cap....
why not leave the dirty "dirty side" with small holes PCV in the engine, the fact that the holes are gunked up, means, will less crankcase gunk will flow thru it,
Resulting in less carbon build on intake valves...
2012 Traverse with Elite E2 X catchcan
Three Equinox with 2.4 engine, 2013, 2016 and 2016
2017 equinox with 3.6 engine with Elite E2 X catchcan