The main bolt on my alternator will not budge.
I don't think this has ever been removed.
Hex head has damage.

What are my options to remove this thing ?

TIA

 

soak it with penetrating lube everyday for a week or heat the devil out of it.

 

Heat the place where it passes through the alternator housing with a torch while you're trying to turn the bolt. These can be really stuck tight. When you put it back together put some grease or anti-seize on the bolt.