I'm working on it but my notes have lied to me.
Yeah, no clue -- I've been scratching that itch for six years now, and to show for it just have a lot of raw skin at this point... I've always presumed it was a two-part greeblie comprising an airplane landing gear piece (right side) with one of the (6) rear-of-engine angled nibs making up the left side. To be specific, the closest guess was the idea that the nibs came from the small (not medium, not large) Roco 1/87 Z-132 Sperrhindernisse Antitank Obstacles kit (which gives you sm, med, lg in each kit), and the airplane piece came from a modified section of the Airfix 1/72 Heinkel He-177 landing gear covers: but NEITHER of those is actually correct, even though they make an "okay" substitute if you're desperate. I think only Dave Beasley actually "knows" as he's the one who first "realized" the Y-Wing from Joe Johnston's revised drawings of Colin Cantwell's original prop design, and first built it into a prop with, presumably, the Red Jammer Y-wing. But he's famously not available to answer e-mails, even though I'm told he's alive and well, but simply leads a very private life at this point. So long story short, it's a serendipitous moment still waiting to happen, and as far as I know, neither Msr. Tox nor Steve Neisen nor any of the other original gangsters of the hobby have figured this particular section out -- but I could be wrong, as always, and they could simply be keeping these secrets to themselves.
That's some cool stuff there Craig!