Routing small parts is dangerous, so the best approach is "don't bring the piece to the router; bring the router to the piece."
First, I screwed the template to a scrap that was clamped to the bench, but I discovered that the roller bearing nut was hitting the scrap. So, I had to put in another small scrap to get some height.
Then, I laid down 2-sided tape, but kept it away from the edge to avoid gumming up the router bit, and stuck on the rough-cut piece:
A quick but carefully spin with the Colt router and it looked decent:
At this point, I kept the piece mounted for stability for finishing. I cleaned up the chatter with a fine file, then polished up with grades of MicroMesh.
Now, for the dozens of incredibly talented builders on this forum, this is a total hack job, and I'm aware of that. Just sharing what worked for me, and I truly enjoy learning from the experts here.