Lure choice is a matter of trial and error. Start by matching the size and profile of the predominant bait fish. Lindy Shadlings and Storm Thundersticks work well also. But, experiment with size, shape and color. Brighter lures work best in stained water, natural colors are best when clarity is good.
Speed can depend on water clarity, too.
If clear, try 2 mph. Faster speeds may trigger strikes when slower speeds will not. But remember, the depth that leadcore runs is very speed dependant. The faster you go, the higher it rises. If water is dirty, try 1 mph as a starting point.