This is the second cover that I have installed the oil pickup fitting into. The cover comes with the holes pre-drilled. I used the pilot hole provided for locating the port. As shown in the first photo below, the pilot hole is drilled just a little too low as compared to the gasket. This mismatch becomes even more obvious when you enlarge the bore to 13/16" for tapping the threads.
I didn't check the alignment to the actual sump gasket when I drilled the first cover and the oil pickup opening was obstructed. Nearly a third of the opening was not available for oil to flow through. Unless you check it against the gasket it would be an easy thing to miss.
The second cover that I ordered had the same problem, but at least I was aware of it beforehand. I could have weld filled the mis-drilled pilot hole but I decided to use a thick steel plate with a hole drilled into it as a drill guide. After marking where the hole should be on the sump cover, I clamped it securly to the drill press and took it slow and easy. The result is shown below in the third photo.
