Complete all of the Main Table adjustments before you worry about the Extension Table. ...Follow the steps in the manual religiously.
I think I did that.
Using a combination of the original manual that came with my machine and the current downloaded manuals, I did align the main table with painstaking patience, taking my time over two days, following every step. Even went out and bought a Mityouto (sp?) dial indicator and took the advice to start with leveling my SS. After leveling the whole unit, I started making the table parallel with the sanding disk in the drill press position (sanding disk marked for the high spot). After many adjustments, I got the table within .004 for that task. Secondly, I set the 90 degree postion stop (drill press position), accepting .004 there too. Then I returned to sawing positon and got the miter slots within .002 again using the high spot on the sanding disk. Next aligned the rip fence and that was dead on. Then I put a saw blade on the spindle and set the table to 90 degrees a 4" engineer square. (I had already tested the square by drawing a line on paper against the square and flipping the square to draw the second line. The lines were parallel to my eye.).
To get comfortable with the main table, I moved the table up and down, back and forth, tilted right and left, moved the headstock back and forth. Tested all the measurements again, and they were within the same tolerances as I first locked in. I admit I was amazed at this.
Now I'm on to the the extension table where I ran into my current unresolved puzzlement. With all the other alignments holding so well, I couldn't fathom how the extension table could be so far off plane when compared to the saw table. That's the only thing that's casting suspicion on my original saw table tilt alignment. If that's off, then I can understand how the unshimmed extension table is off so much.
So, at this point I'm wondering if I properly aligned the tilt of the main table to the saw blade. I know the sanding disk has high and low spots, and I imagine the saw blade does too. Using the square against the face of those items seems nowhere as precise as the dial indicator that clearly reads .001".
Obviously, I'm not ready to proceed with the table extension alignment until I'm comfortable with the main table situation. What do you think? Am I not thinking this through right?
I appreciate all the help.