Almost everyone makes the mistake of using the full stereo image for the Leslie Sim. The Hammonds sim (which, like 99% of sims including the ventilator) is two dimensional - in other words shifts from left to right) it is vital to run the sim through a mixer, take a look at the position of the keys on stage and then 'pan' the left and right channel to that point.
Now, that is a good idea. Thanks TWD, I didn't know about "panning" the sim channel in regards to where the keyboard is located.
I learn something new every day.
Ian