Toller wrote:
I adjusted and squared everything. When I flip my pieces over and put them
back together they fit perfectly. Except...

The table is flat, but when I move the arm to 45 degrees, both right and
left, the blade is a sixteenth close to the blade then when it is at 90
degrees. This doesn't make any sense to me; it is like the arm droops a
sixteenth when I turn it.

Any advice on what this is, or how to fix it. Or, does it even matter?
Unless I am cutting a diagonal dado, it probably will never make a
difference, and I have never cut a diagonal dado. Any other times it would
affect the results?

Your table is not level. Flat? Maybe but not level.

IIRC (only have to go through this drill when I replace the table of the
saw) remove the blade from the saw. Rotate the head so the arbor is
pointed downward. Loosen (so they are just snug) all the metal brackets
holding your MDF or plywood top to the RAS frame. Now, crank the arbor
down until it just touches the top. Move it all around and level the
top in this fashion. You'll likely find two (maybe more) set screws in
the field of the table that allow for adjustment over the inner support
members of the RAS frame. Adjust the table in this area in the same
fashion using the screws to raise/lower the table.

Once everything is "level" tighten down the mounting bolts on the sides,
etc.