MAINSHAFT NUT TECH TIP
The 901 mainshaft lock tab (999.038.001.00, top) is no longer available from Porsche. You can use p/n 930.302.453.00, 930 mainshaft lock nut, which replaces the lock tab and nut and can be staked down.

Compare the NLA lock washer (top) to the replacement 930 nut (bottom).