Sorry guys, I never got back to you all on this with the "solution"
When it first acted up, I tried aligning/balancing the actuator. I could never get closer than .030" runout.
I ended up pulling the actuator, cleaning surfaces, and checking stuff out. I now know how that critter works
But in the process, I found the castle nut on the back of the mounting flange loose. I tightened that up, then went about re-indicating the actuator and BINGO!
She runs smoother that she ever has since I got her. I used to never go above 2500 RPM cause it vibrated more than I cared for and NEVER went to 4000. Now, I can run 4500 and she is smoother than she ever was at 2000.
So all is well... and it was basically an alignment issue, and appeared to be rooted in a loose castle nut.
Thanks again for all the help and suggestions!
Wade