I gave up fishing a few years back (not sure why, no real reason) but nothing ever worked as good as a Mepps spinner. The action is second to none and they'll spin better than any other even with a very slow retrieve.
I have a tiny Mepps #0 1/8 oz spinner that's caught dozens of sunfish, bluegills, crappies and even a 3 lb largemouth bass. It's been snagged a bunch of times, but I always got it back and never broke the hook. Most of the paint is gone (used to be red with tiny yellow polka-dots), with a black spinner blade.
It's one of my most prized possessions.
That takes me back, Woody. The smaller Mepps caught not only the sunfish, specks, and bluegills, but, like you wrote, large mouth as well. Once in a while, went all out and had the one with the plastic minnow, but that was not as good. Canadian AF used to include Mepps in survival gear. Don't know if they still do.