The serpentine belt setups run the water pump backwards on the LS1 as well. I ran up against this problem when I wanted to tidy up my belt setup.
The Ford motors at least have the option of running a conventional rotation water pup from the earlier model. It shouldn't be to hard to fabricate another mount for the crank angle sensor.
Just reversing the rotation won't work because the impeller will be pumping the water round the wrong way. You could try what I did and machine up an impeller with the vanes running the other way.
Here's the one I did for mine
Cheers