What makes you say your azimuth is "slightly off"? Is the headshell not parallel to the platter surface, when viewed from head on?
Simao, Shims could be used on one side of the top of the cartridge, as a wedge between cartridge body and headshell undersurface, to correct for azimuth. Perhaps that is the intent.
The thing about having azimuth adjustable via the tonearm is that it also affords the user the opportunity to get it wrong. As MC suggests, very often adjusting the cartridge body at an angle to the LP surface, in order to optimize the electrical readouts of channel crosstalk and phase, will also sit your stylus tip at a subotimal angle to the groove walls as regards its physical contact patches. This is "not good", because it leads to uneven stylus wear and distortions that may be more noticeable than suboptimal crosstalk or phase anomalies. I do own 2-3 tonearms that permit easy azimuth adjustment, but in recent years, I have settled on the paramount importance of having the stylus sit "square" to the groove walls, over all else.
But if your headshell is fixed at an angle other than parallel to the LP surface when viewed from the front, I would suggest doing something simple to fix that and then stop worrying.
Simao, Shims could be used on one side of the top of the cartridge, as a wedge between cartridge body and headshell undersurface, to correct for azimuth. Perhaps that is the intent.
The thing about having azimuth adjustable via the tonearm is that it also affords the user the opportunity to get it wrong. As MC suggests, very often adjusting the cartridge body at an angle to the LP surface, in order to optimize the electrical readouts of channel crosstalk and phase, will also sit your stylus tip at a subotimal angle to the groove walls as regards its physical contact patches. This is "not good", because it leads to uneven stylus wear and distortions that may be more noticeable than suboptimal crosstalk or phase anomalies. I do own 2-3 tonearms that permit easy azimuth adjustment, but in recent years, I have settled on the paramount importance of having the stylus sit "square" to the groove walls, over all else.
But if your headshell is fixed at an angle other than parallel to the LP surface when viewed from the front, I would suggest doing something simple to fix that and then stop worrying.