mc1984ss,
I understand the hesitation on drilling holes in $800.00 valve covers. I carefully measured out to get an area that wasn't in direct line with the rocker arm to reduce oil splash into the breather. I used an open hole grommet but fabbed my own baffle out of thin aluminum making sure it wasn't to close to the hole to allow oil to flow freely into the engine. I used panel bond adhesive (the body shop stuff not JB weld) to attached the baffle to the valve cover because I didn't want to weld to the covers. Though I had some photos of the underside but can't find them now. Its really not that hard after you punch the hole
BB