Problem solved -
The first time I changed only the bearing - I think it may have been damaged when it was removed from the knuckle. The guy at the junk yard said that a used bearing needs to stay with the kunckle since it has been "worn in".
Regardless, I got another knuckle / bearing assembly from the junkyard and changed the entire knuckle / bearing assebly as one piece. The two bolts on the strut were a bear to break loose.
While changing it I noticed the lower ball joint was a little loose, so I bought a new one. It took a little while to drill out the rivets and chisel the heads off.
So, now there is no hum and I must have gotten the alignment very close because it tracks straight. I will watch for improper tire wear.