Got it. Let finger soak in vinegar for about 30 minutes. It really softened up the callus and I was able to find the head with needle. I'm pretty sure the vinegar drew the splinter nearer to the surface, it was easy to find whereas before it was nowhere to be seen, even after picking fairly deep. Pulled out with a good set of tweezers. Darn thing was 3/8" long and went nearly straight in. Had to be close to coming out the other side.
Got it by smoothing a bead of caulk on trim with my finger preparing for paint. I hate painting.
