No the way it's done is for the guy in the a/c to turn onto his cardinals using his instruments. The guy outside with the landing compass then calculates the error on the a/c instruments. So say you lined up on 360 using your HSI, the guy outside measures your heading and finds that it's actually 358. You then do your other three cardinals and calculate the error (it's not even all the way around). All the pilot has to do is line up the a/c accurately, the techy does all the calculating and adjusting. You adjust the flux detector which is usually somewhere in the wing by physically turning it and then you do an eight point check swing and then calculate your compass card errors, being as a compass swing never actually removes all errors.
Well that's how I used to do them, it's probably done by computers these days.