Clockwise rotation when viewed from the flywheel/ignition system end of a full-crank mower engine is normal. It gets a bit tricky with half-crank engines, and with car/truck engines, which have the flywheel on the output shaft end for obvious reasons, but they still rotate clockwise when viewed from the opposite end to the output shaft.
If you hold the crankshaft stationary with the keyway on top, anything that moves the ignition cam clockwise then locks it to the crankshaft, is advancing the ignition (because it results in the points opening sooner, relative to the crankshaft).
I can't see from the picture whether the ignition cam is on a parallel section of the crankshaft, or is on a taper. If it is on a parallel section, you appear to have a choice of 4 different ignition timings. Compared with the timing as it's set up in your photograph, you can retard the ignition about 30 degrees by using the other keyway in the ignition cam. Alternatively, if the cam is on a parallel section of shaft, you can pull it off and put it on flipped over. That would give you two more ignition timing options (one for each keyway position), both of them considerably retarded from the position you have it in at the moment, because they move the active part of the ignition cam anticlockwise relative to the crankshaft. However, because I don't know where the piston is relative to Top Dead Center when your picture was taken, I don't know which of the four positions coincides with 25-30 degrees before TDC. If the keyway is at TDC (which is fairly usual) the setup you have in the picture would give you ignition timing of about 25-30 degrees BTDC.
Note that to get the ignition to operate, you have to choose whichever of the two flywheel keyways results in the magnet in the flywheel passing over the ignition coil at the moment the points break.
The two key positions in that flywheel are not at right angles to each other, so they are alternative timing positions, not a provision for using two keys simultaneously. The angle between the two flywheel keyways appears to be about 60 degrees. After choosing a keyway for the cam to give you the required ignition timing, you should then choose the flywheel keyway that results in the magnet passing over the coil simultaneously with the points opening. There is probably only one combination of key positions that will result in a spark happening at all, and it will be about 25-30 degrees before top dead center, depending on the size of the breaker point gap.
