No can do!!
Spotwelded into place.
THey're actually called baffles or oil seporaters. Designed to keep the oil in the cover and only allow the vapor to escape with the pcv.
You can use baffle/grommets in your new covers to do the same thing.
http://www.speedwaymotors.com/PCV-Gr...Caps,7332.html
What are you using for new covers?