First, get a map. There are shallow spots away from shore when the lake is drawn down like it is now, and a lower unit is an expensive way to find them.

It's going to depend on the weather. Been cold, so I'd expect them to be deeper. I usually start at 12ft if I don't have any indication what they are doing in the spring. Minnows on a Kentucky rig and/or 16th oz jigs with black/chart or yellow grubs/tubes.

What part of the lake are you going to?