Wow, I've never seen that long of a set-up on a Mopar. The alignment is very important for belt and component bearing life, but also to keep the belts on the pulleys at higher engine speeds. You also want to maximize belt wrap on the pulleys.

I'm of the mindset that anything different than perfect alignment is less than ideal. My Mopars have never been belt throwers though, and I've run them at much less than ideally lined up back in the day.

These days, I get them straight as I can by visually aiming down the pulleys along the length of the belts. They make pulley spacers, and you can get creative with your bracket mounting. Be sure to minimize any bracket deflection while you are at it.