If you rotate the front housing 90 degrees counterclockwise (as you look at it from in front of the plane), the timing will be correct for clockwise rotation ('Pusher' prop direction). The actual timing numbers (for the crankshaft) of the K&B .40 are open at 35 deg. after bottom dead center and close at 45 deg. after top dead center which is 190 deg. total. Rotating the front end, and measuring in the other direction, it opens 45 deg. after bottom dead center and close at 55 deg after top dead center. Represents a 10 degree shift, but still 190 degrees total. This was what I just measured on an older model K&B like the one in the OP. (I think that is the 8011 model).
Other makes of engines will have slightly different numbers, but they would still be close (enough to run, anyway).