If you are having crankcase pressure issues, the STM Dipstick Vent may be able to help. This features a -6AN fitting welded onto the dipstick for ease of venting the crankcase.
Venting the block is better than the head as it will allow your oil to return to the pan faster. The air that vents out of the valve cover rushes up from the block through the oil return passages causing the returning oil to slow down and sometimes push back up into the head leaving the pan dry.
