The bell housing on a 59A was an integral part of the block, so there was no separate bell housing as such. The '49 through early '51 Mercury's had a different pattern on the back of the block that was the same as all 8BA type engines. They did however, have a separate stamped steel bell housing that had the 8BA pattern on the front and the 59A pattern on the back. These are sought after when putting a post '48 flathead into an earlier vehicle.