That hole goes to the bottom. It is to let any oil that happens to make it past the front bearing drain down the front of the transmission, instead of out the front of the retainer and onto the clutch.
If it goes in any position (symmetrical bolt pattern), that must have been before they idiot-proofed the way things go together to prevent mistakes on the assembly line. One bolt a little out of position in the bolt circle would to the trick.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.