Taller covers with baffles. Make sure you get covers with baffles. I suggest you get a clear picture of what you are doing with the PCV and/or venting system. Open breathers spray
oil all over the engine and car.
How many RPMs are your turning? A stud girdle is good for high spring rate, long travel, high RPM use and unless you are turning in the 7500 or more range with something like a D221, I would look at putting your money into a few other areas.
Just my opinion.