The sliding sinker rig is best, using the little yarn ties you can buy for just this purpose. By sliding and re-cinching up the yarn you can rig your bobber to drift at any depth. Yes, the best presentation is a cut-plug rigged to spin slowly under the bobber.

But you don't need to drown bait to catch silvers. Throw any jig, cast a spoon or spinner or toss a fly and you'll do just as well (and cover more water while you're at it!) and have more fun fishing.