Diagramming Noun Adjunct-Heavy Sentences

I learned to diagram sentences from my mother (a Linguistics major in college), but didn't appreciate it much at the time (to be fair, my mother didn't appreciate it either until she began teaching me and my sister). Until, that is, I ran across a sentence in the local newspaper that made me want to diagram it.

The sentence in question was “This is not an administrative license revocation matter.” (It has to do with the ongoing investigation into whether the mayor of Hilo inappropriately used government funds for personal benefit.) It's not particularly long—no complicated compound sentence or anything—it was merely the noun phrase in the predicate that attracted me. It took me quite a bit of research, though, to figure out what all those nouns near the end are.

The ending noun phrase “administrative license revocation matter” has what looks like a couple of nested noun adjuncts, which is where a noun modifies another noun the way an adjective normally would. “Administrative” is an adjective modifying “license,” which is itself serving as a noun adjunct modifying “revocation,” which entire phrase is modifying “matter” at the end.

And yet, nowhere could I find how to diagram something like that. One website helpfully told me that noun adjuncts are diagrammed like adjectives—on a diagonal line beneath the noun they modify—but I couldn't see any way to chain multiple noun adjuncts together.

After some time pondering the matter and scratching my head, I decided to pull a mathematician trick reformulate the sentence into something with a prepositional phrase: “This is not a matter of administrative license revocation.” Written this way, I can just about diagram it, though I'm not 100% sure about “administrative.” I ended up diagramming it as you would an adverb modifying an adjective because it looked nice and seemed similar, but I've no idea if that's correct. Anyway, here's what I eventually ended up with:

If any of you out there are more familiar with sentence diagramming and would like to point out how it should actually be done, feel free to sound off in the comments! A hui hou!