Nuova Simonelli MDX Burr Alignment

[saeco_user]

I recently purchased a Nuova Simonelli MDX (64mm Doser) grinder second hand for $300.
It was very clean and looked to be in very good condition.
However I am unable to grind fine enough for espresso as the burrs touch significantly as I adjust the setting finer.
The burrs looked to be very worn and I replaced with a new set ($60) that are, as expected, noticeably sharper, but I still have the same issue.
The spindle is dead straight and when spinning between calipers I can detect no wobble.
The top burr carrier also looks to be in good condition with no damage or deformation.
From it's level of cleanliness my guess (hope) is that it was pulled apart and re-assembled incorrectly.

Before I go ahead and dis-assemble myself I thought I'd check to see if anyone else had suggestions for the burr alignment issue.
Thanks

[level3ninja]

Might need shimming under the upper burr. You could also try rotating the upper burr around the mounting holes to see which orientation works best.

[saeco_user]

Tried rotating burrs and also burr carrier without significant difference. It seems to me to be too far out of alignment for shims. My reasons for this are a) I can't get close to an espresso grind, the burrs would be grinding each other before this occurred, b) I have a cheaper, lower tolerance grinder (noticeable play between lower and upper burr carriers) which I easily can grind for espresso with only the occasional "chirp". I will try shims if I can't find anything else wrong.