Alpha one Gen 1 anode replacement

[redmen62]

Thought I'd replace my anodes and impellers this year since I have no clue the last time they were done on either engine... and of course it's turned into a little more of a head ache than I was hoping for. Apparently the previous owner didn't believe in preventative maintenance. The head for the anode on the front of the cavitation plate is so stripped the allen key slot is completely rounded off and there's nothing for the allen key to grab to get the bold lose. Since the last bolt to separate the upper and lower, I have to get it off

Any ideas how to get the anode off without being able to turn the bolt? Can I somehow spin the whole anode, drill out the bolt from either the top or bottom?

 

[Bt Doctur]

You can try hammering in a metric allen key other than that start drilling the zinc away little by little