Where can I find the regulatory guidance for the proper way for a commissioned officer to address an NCO?

The LTC. kind of beat me to the punch lol.

Should I happen to cross paths with LTC Curlee I would address him as "Colonel Curlee" and not "Lieutenant Colonel Curlee" no more than I would want anyone address me as Sergeant First Class Bruorton. Except in official orders, recommendations for awards and certificates, it would simply be "Sergeant."
"Colonel Curlee" has a nice ring to it.

Correct, unless you run into a EGO problem . sign 40 yards

SFC Greg Bruorton, you are absolutely correct. That's why I would address Staff Sergeant Wise as Sergeant Wise, and he would address me as colonel. However, I think Marines always address each other by their complete rank.
I always thought that "Colonel Curlee had a nice ring to it also. However, I've been retired since MAY98, so those days are long since past!

Nailed it. In addition, DA PAM 600-60, Table 6-1 provides a good overview from a protocol perspective. Always a good idea to cite to applicable publication as violations constitute a possible Article 92 infraction.

There you have it ! Thank you all who helped !

Thanks for providing the regulations SSGT Wise can cite to gain compliance by this officer who obviously doesn't respect the NCOs that work for him. These NCOs have earned their rank just as he earned his and that deserves acknowledgement, especially in light of the fact it has been brought to his attention that they prefer him address them by rank. He may think that he is creating a 'relaxed' atmosphere, but the example he is setting will filter down through the ranks so that the enlisted personnel working for these NCOs may adopt the same attitude which may undermine their authority. It also sets up those same junior personnel for disciplinary action when they follow his example which is unfair to them.

I was at Notfolk base terminal waiting for a flight down to Myetle beach and I acknowledged their presence as protocol
Calls for. These guys were absolutely snobby.. A Navy Chief who'd witnessed the exchange went into the back and came out with a Navy captain.. they both went over to those Lts and the Chief backed off
And the Capt. invited them into his office...
A few minutes later they came out and the Captain was with them.. they came over and apologized for their snobbery when I acknowledged them... I never expected that... it was cool !

good answer, I've served a couple of times in Wing Engineers but not in a squadron, have heard that sometimes the pilots use first names with enlisted, maybe just a few such as their crew chief and only one on one, a little less strict, low stress

I was on embassy duty when a Army major addressed me by my first name so I said "Well good morning to you too, Don!" Needless to say he stripped a gear and I was quickly educated by my DetCmdr that it was an officer's prerogative to do that. Fortunately after a lengthy discussing in Army vs Marine expectations, he said he would never address anyone of us by or first names again and even promised to knock out 25 Marine count push ups if he continued to refer to our SNCOIC as "Sarge." Turned out to be one of the funniest military life lessons I ever received!

When I went on Joint Service duty back in the mid 70s, I was told to study up on the customs and courtesies of the other branches. It was a bit difficult to remember to salute indoors when I had to report to the Air Force commander and then turn around and not salute the Marine deputy commander. If I heard an Air Force officer use a first name to an enlisted man, I just ignored it. That officer never called me anything except Staff Sergeant or Gunny so all was good between us. If anyone got upset with first names, it was the Navy Chiefs.