Too much horsepower?

I was wondering how much power a 30 spline 8 3/4" can handle. I was just about to order a new set of Moser 30 spline axles for my new 410" build(close to 600 hp), but I wonder if I shouldn't just get a set of 35 spline axles & matching spool, just to be safe???

......Step it up to at least the 30 spline.................kim...........