Tony,
After you have both the upper & lower screwed in flush, turn slightly further, as explained above. You are not done yet!!
Install a blade and adjust to get 90 degrees to the table. I took an 1 1/2" tall block and sawed into it slightly. Stop the saw, spin the block around and hold it against the blade. IF the blade fits the cut perfectly, you are fine. If it doesn't, you need to start adjusting the loc-tite screw(s)
I started near the end of the block. Each time, after trial and error, I found the perfect adjustment. Now I recheck it after each time the table has been tilted and again before starting a stack cut.
Once you have made the "perfect" cut angle in the block, it can be used forever.
Hope this helps Friend,
jerry