If the valve cover attaches with 4 screws around the perimeter (not 2 studs through the top) there shouldn't be any other holes in it. A very few had four narrow slots in the top for ventilation, but I think the last year for that was 1954.

The original oil routing was from a passage drilled to the rear cam bearing area, and through a tube hidden by the pushrod cover which attached to the rocker shaft connector in the center of the 2-piece rocker shaft. Later model 235's eliminated the tube altogether and used drilled oil passages in the block and head.
Jerry

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