How do I include the actual quiz slide number in a slide master?

I've seen many posts about "how many quiz questions" and "quiz numbering" but I need something different:

I want to add the actual Storyline slide number (e.g., Q1.20) so I can have a quick reference point when someone needs information about a particular quiz question.

I know I can use variables - %Project.SlideReference% seems to be the closest, but it re-orders (and, therefore, re-numbers) the slides based on how they appear in sequence in the quiz, and I then lose the original slide number, rendering that reference useless.

So how do I keep the numbering consistent with what is in my question bank, when the question bank is randomized and not all questions are presented (i.e., there are 25 questions in the bank but only 15 on the quiz)?

Thanks for any help!

--Lesli.