It is possible someone replaced the 4 bolt valve cover with a 2 bolt. Easy conversion. If you pull the cover the 4 bolt holes will still be there. Just my 2 cents.
Saint, some folks just think the 2 bolt is way cooler than the 4 bolt. It was done a lot and you could/can buy kits to do it.
Saint,
Be aware that most 216 and most pre-1955-2nd series 235 valve covers had slots/vents in them. They had non-breathing oil filler caps on the valve cover.
There is nothing bad/wrong about that - but, it is possible for water to get into rocker-arm/top of the head (and, maybe into the oil-sump under the block).
