I'm ordering a new rear axle case from PA Blanchard for my Lightweight, which is a Series 3 and appears to be 1980 or 1981. The part number for the case is FRC3367.

PAB is asking whether or not I want a "Flat Bottom" axle casing. They stated that the later style casing is flat on the top and on the bottom of the axle case. Mine appears to be rounded top & bottom. They told me that they are interchangeable.

Has anyone ever heard of this "Flat Bottom" case? Anywhere to find a picture of one?

Thanks,
Jeff