We did...
I learned that, contrary to my previous opinion, the larger compression ring gap (according to all the "good" information I could uncover, for a turbo application) goes on the second ring, NOT the top one...
Like I said, I learn something every day.](*,)
We ended up with .020" on the top ring, and .024" on the second one.
Hope it's enough (3.465" bore.)
Thanks for your interest!;)