Stock are more than capable of 750 whp and actually quite a bit more with some ARP2000s. When upgrading the best bang for the buck is Molnar by far. Their power adder rods are rated to 40 PSI at 9000 RPM and MSRP around $650.
By the way it's been proven that the factory 8740 bolts clamping force is stronger than the rod itself and is not a point of failure. Switching to ARP 2000 does nothing for increased capacity on the factory rods.