Excellent!

Between these two ideas, I should be able to correct the problem! Thanks, guys!

Reynolds, I think you hit the nail on the head.... Now to see if those nuts are readily available!

Holy jit! Reynolds wins the prize! [I'll send you a box of aluminum foil with your user name printed on it!]

I can slip an .012" feeler between the nut and the stem, around about a third of it's circumference..... I'll try shimming it for now. A new nut will solve the problem.

Any idea what you call that nut- since it's different than the actual nut at the top of the headset?

Thanks to everyone for all the replies...and especially to you, Reynolds!

I'd call it a 1" headset locknut.

"Top nut" seems to be it. Can't find any in alloy though......guess I'll have to get steel for now [at least with the steel, I don't think I'll have to worry about having the same problem again].

I touched a magnet to mine....it's somewhat magnetic; The stem itself is non-magnetic of course (AL) and the spacer and the actual lock nut under the spacer are very magnetic (definitely steel there..which surprises me, for a quality bike).

Gonna try this:
https://www.ebay.com/itm/Tange-Seiki-...item589a2c6c09

Good friend of mine had that creaking noise and could not figure it out. On a tour one day he hit a bump and the steerer tube broke off at one of the threads just below the headset. He broke his collar bone. Looking at it later we realized that was the source of the creaking due to the corrosion on half the cracked off thread. Pull it apart and inspect to be sure all is A-OK.

OUCH! I will definitely be taking a look! Couldn't hurt to check it and lube it, anyway. Thanks!

Thanks everyone. I've been fighting this problem off and on for over a year. I fixed it by putting aluminum tape on my quill stem and greasing the inside.