Delco 10SI confusion

[tomfg]

My truck had a Delco 10SI on it when I purchase it. Upon installing a voltmeter in the dash, I noticed it was charging between 14.8 to 15 volts all the time, which I understand is on the high side. Tried various things mentioned on the forums, ie., installing a "generator light" in the #1 "exciter" wire from the ignition switch, moved the #2 sensing wire to the horn relay, etc. (it was jumpered to the back of the alt.'s "bat." terminal.

Anyway, those fixes didn't lower the voltage at all.
Rebuilt the alternator with a kit, and no change.

Purchase a rebuilt alternator, and I figured it's nice to have a spare
anyway. It's still charging just as much, and when I stared up the truck
onces yesterday, the voltage meter pegged out to 16 volts for a couple of seconds, then dropped down to 15 volts.

I went on a 90 mile "shake down" cruise yesterday to see how
everything did, and I ran the headlights and heater blower
the whole time, as I'm afraid of boiling the battery.
Of course, it appears I have a "maintenance free" battery,
and I can't pry off the top plate to check the acid levels :-)

Am I possibly overlooking something in my wiring that
would make the voltage operate so high, or am I
worrying about nothing?