First, thanks for the reminder that I needed to take my tailstock apart for cleaning and lubrication. I normally do that a couple of times a year, but had forgotten to do it so far this year. Not a big job - takes less than 10 minutes, but really makes using the lathe more pleasant.
I grabbed a couple of pictures of what the tailstock ram and casting on my Turncrafter look like.
As you can see, the hole in the ram is perfectly centered, and when the ram is removed, you can see all the way through the matching bore in the headstock.
The ram doesn't rotate, and that hole receives the drive screw. The other end has the Morse taper, and as Rick says, it's probably machined from that end. But I agree with Hank that if the hole for the drive screw is not exactly centered on the the axis of rotation, tightening the handwheel will apply a force that will try to shift the ram off the turning axis (and in Joe's case, to about the 4-5 o-clock position). I suspect that the live center would compensate for that in normal turning, but when you mount a jacobs chuck for drilling, it's axis (and hence the axis of the drill bit) will align to the ram. The consequences could include stiff operation of the handwheel, and possible problems when drilling.
So as Hank said, I suggest getting on the phone with PSI. My experience with them has been outstanding, so I would expect them to jump on this problem immediately.