05-21-10: Smoffatt
Thanks for all the responses and tips. I have installed 2 little brass washers between the A90 and the headshell and tighten it down. I will give it a listen.
The cartridge is now perfectly level as none of the 3 tabs are touching now.
I think that's a good solution - though exact levelness with the head-shell is hardly an issue with the Phantoms azimuth adjustment.
I'm sure it will sound great.