What is the Best Tool to Measure Cartridge Azimuth?

What do you use to measure / set azimuth of your cartridges and / or styli? I am afflicted with diminished eyesight, so aligning the azimuth of the stylus by eye is not practical.

To that end, I’ve use a simple bubble level (spirit level) about 1-1/2” in diameter to get the headshell as close to level as possible, after first leveling the platter by adjusting the turntable feet. 

I figure some clever lever engineer has made an easy to use electronic tool for this purpose, but I haven’t found anything in my searches. Nature abhors a vacuum, so one day if not already, it might surface. 

Until then, does anyone have alternate methods? How about using a test record? Is that feasible? I do have a couple of good oscilloscopes by the way, so I can make precise measurements of levels, phasing, frequency, etc.... 
I second the use of the Foz and its accompanying test record.   The results are super
AnalogMagik looks intriguing but having to spend $750 plus another $75 plus tax, and no support unless you buy a “$150 Lenovo” from them seems extremely suspicious. You simply cannot get a usable laptop for $150. Their literature is written by someone who is borderline illiterate, which also seems their product seem as genuine as an email from a Nigerian “prince” who has millions of dollars for you. 
The Fozgometer ostensibly could be replaced with a decent oscilloscope, so what is it’s benefit to someone who already owns a couple of high-end oscilloscopes? Don’t take my question as being combative, I’m just curious if the Fozgometer has any unique qualities that lend it to being better or easier to use for the task. 
The most accurate way is an oscilloscope. Using a Fozgometer is second. My problem with it is the price. Both methods align the coils with the record not the stylus. If there is one manufacturing inconsistency that worries me most is the stylus not being properly aligned with the coils, an easy error to make. The above methods may result in the best sound but I prefer the least record wear so I use the mirror method lewm referred to above. That gives you a stylus aligned to the groove and you can't beat the price. I do add loops to the process.

I am in agreement with those who prefer that the stylus be properly aligned to the groove over a correct electrical alignment.  With my current setup, I used the mirror approach to get a decent visual alignment of the stylus to the groove.  I then used a Fozgometer which indicated such a small change that there was hardly any change to the visual alignment (good for me that the cartridge was built so well).