I've heard the first limit on the Hemis isn't the valvetrain but instead the harmonic balancer on the crank. It's been known to fail as low as 6400 rpm I've heard. That's why my rev limit will be set at 6300 when (if) they ever release a tuner.
Also, as far as setting shift points, to make a fairly accurate guess, some math would have to be done for each gear change, as well as knowing your peak horsepower. Each gear change may need to be made at different points in order to keep you nearest the peaks for the longest amount of time. Also, forget torque peak when drag racing. Hp peak is where you want to stay. And before anyone yells foul, remember HP is just torque relative to rpm.
In my case, my power peaked around 55-5600. This means the perfect shift from first to second would be around 62-6300. But wait, that's only assuming that the power drops off after peak at the same rate it rises to peak. That's probably not the case and if I had to guess, these trucks would probably do great shifting at 6500. I won't do it, but you guys feel free.