Tom, as noted the Eagle shafts are not phased.
It has been a ton of years since I did driveshaft research.
The ideal goal is to have the input and output shafts parallel. In that configuration, the shaft does not need to be phased (U-joints not at 90 degrees for each end of the shaft.
The problems begin when the shafts are not parallel. Sounds like that is the case in your bus. As I recall, there is design process that lets you "calculate" the phase to help offset the velocity "fluctuation" of non-parallel shafts. As I recall, the phasing only helps to a certain extent. My tired old memory does not recall much more that 10-15 degrees phasing and nothing like 45 degrees.
Many of you have seen the hugely lifted 4 wheel drive vehicles where they rotate the pinion of the rear end up perhaps 30 degrees. The rotate the rear end up to keep the standard U-Joint angle to less than about 5 degrees (about max for any reasonable life). Then the put a constant velocity U-Joint on the transfer case to avoid the velocity fluctuations that would be severe in a standard Cardan joint.
I tried to do a bit of research for this reply and quickly figured out that my memory made the engineering concepts much simpler than they really are.
Wiki has a couple of decent pages:http://en.wikipedia.org/wiki/Universal_jointhttp://en.wikipedia.org/wiki/Constant-velocity_joint
Way more information than you asked for, but what else would you expect from an engineer who is addicted to minutia.