Adjusting the output voltage on the alternator

When we came up from Newcastle with the brand new batteries I noticed that at one point the voltage had got up to 14.8 volts.  The alternators are supposed to put out 14.4 volts and the batteries are ok with this.  As soon as the engine turns off it settles back down to 13.6 volts and then as the batteries are used it will drop down to about 12.5 volts and then we charge again.
That's how it's supposed to work.
Anyway, I've just spent some time with both alternators out and like a lot of other things on this boat we find that things are not exactly the same on both sides and not the same as the original manual says they should be either.
On the starboard side the alternator was putting out too many volts and I've discovered that on that side I have an externally adjustable voltage regulator.  Looks very much like this.

Anyway, some very careful adjusting with a jewelers screwdriver and the voltage is back down to 14.4 volts.  Very happy now.