Cookie, Steppers, Thornley, others?

Whilst fixing the gearbox on my R90S, I decided to change the rear brake shoes whilst the rear end was stripped. However, on refitting the shoes I've turned the cam so that the flattened edge of the cam is now at the bottom rather than at the top (please compare attached before and after photos). Please could you let me know if this flattened edge should be to the top (or to the bottom) or if it doesn't matter?

Thanks.

haynes manual notes that it should be flat down as in your second picture.

Cheers Cookie, thanks very much. Whoever changed the brake shoes last time around must have gotten it the wrong way around.