The oil that runs through the alt. is 1 in the same for the engine. The left over metal crap is more than likely in & all over the engine galleys? U might get away with a quick clean and flush, change the alt.?
Me, I ride to far.
I don't know why the local mechs. don't drop the oil pan. I have dropped my ST pan 3 X's now. Clean the 2 pump screens. Take a mirror & light U can see the rods Bottom pistons & cylinder walls