Well, here's what I'll call "Proof of Concept." Printed it out flat side (the side with the little projections) down - and, as noted, had a lot of support structure to peel off. Nevertheless, it is totally functional in present form (with a bit of light sanding).
I thought I could flip it 90 degrees in Cura, but that was a no-go. Now that I know it will function as intended, I will do the "flip" in TC, so the "flange" is flat against the bed, and I'm pretty sure I'll get a usable, and cleaner, product. I added little wedges on the bottom side of the little nubs to, hopefully, make it print with less support structure.
First shot shows finished product, second shows it temporarily clamped on place (upper left corner).
Appreciate the advice.