My 55.1 Chevy still has the factory vented valve cover (2 vents at the front & 2 at the back). For those that have retained their factory vented valve cover what are you doing to keep dirt and insects out? Have some replaced the factory vented valve cover with a new non-vented valve cover in conjunction with using a vented oil-filler cap? If so, what brand cover did you utilize? Thanks in advance.