Many people say they damage or destroy the rear bearing lock rings when removing....
I just bought a MAC tool AS1929 tubular spanner wrench. It is six prong wrench and is about 1mm wider than necessary. A little filing and it will fit Alfa. For 3/4 drive .
that tool is a front wheel bearing tool for ford dodge and chevy pickup trucks. it will work but whatever you do, do not buy the retaining nuts from iap as they will send you some new style piece that will need a different tool. centerline has them.
vittorio