I went through the same BS with my 7000RPM 408. I have found, the factory bracketry, likes to flex and wobble too much for my liking (or for belts to stay on for that matter)
the power steering pulleys are thin, and easy to bend/warp. i threw them constantly at high RPM. (until i dumped PS altogether)
i do still run an alternator on the car. once the alternator gets to spinning, it puts out a load on the belt. if it's not perfectly aligned, it walks also, and usually throws.
We sell a small, milodon crank pulley, to slow the alternator belt down, and prevent throwing of the belt. It's the "cheaper" fix, than buying an entire serp setup. Sounds like you're a machinist. Dunno if i'd fire up the lathe for $70.lol
http://paceperformance.com/i-842271...ft-pulley-moroso-performance-64700-mopar.html