I have my 200-4R apart for a rebuild and didn't notice this until I looked at the pic I took. Check out the upper left part of the pic. Round hole but half of it looks deformed and has cracks. Is this a major problem? Do I need a new case? What is that hole used for? The trans is from my 87 GN with only 43K miles and I'm the original owner. I did have the trans rebuilt some time ago, could that be from when it was rebuilt or did it come from the factory like that? Almost looks like a casting flaw.