TOPIC: Evinrude Water Intake Question

I'm restoring a 1961 Evinrude Starflite III The water intake plate is mounted on port side of shaft housing just above the cavitation plate. The plate that came with the engine was altered so I hunted up a used one. When it came in the mail, I saw that the intake slot and screen were about 10% of the area of the plate on the engine when U bought it. I looked a little closer at the plate and realized that was substantially altered apparently to allow more water into the shaft housing. (see attached photo. The grey plate is what came on the engine and the white one(probably from a Johnson of the same vintage) is the replacement part.

I'd like to use the new plate I bought, but now I'm wondering if there was a cooling issue with this engine that necessitated allowing more water into the shaft housing. Any ideas out there?