[storm9c1]

Yeah, alignment seems OK. Belts are forgiving and can withstand a little bit of misalignment. But a cracked bracket (as mentioned) could cause an accessory to flex into a worse position under load. So definitely check for that.

I don't like how that belt is riding through the alternator pulley. As mentioned, something is causing a slight twist and ride too low in the groove. That particular pulley looks like it's made for a wider belt. Whereas the water pump pulley seems right for that belt width.

If you watch the WP and crank pulleys turn as the engine idles, do you notice it being out of round or wobble at all? What about the alternator? You said your old alternator was doing this too? So swapping pulley's won't matter.

But I do like the spare pulley that you were holding in your hand in that pic. Can you try that one?

There is such a thing as too tight. Lacking a belt tension gauge, the next best thing is to push on the belt in the middle of the longest run with your index finger and you should feel strong resistance at 1" flex. Meaning it shouldn't have any more flex beyond 1" pushing with a finger. But should allow up to about 1/2" of flex. Any less than about 1/2" on a used belt means it's too tight. A brand new belt may have as little a 1/3" flex but once run, even once, it's now considered used. This is all a generality but is a reasonable reference to start with. FSMs usually call out their own methods of testing proper tension for each accessory.