If there is any way you an afford a guide (assuming there is a good crappie guide on that lake) it would be well worth it for you to go out for half a day and learn where and how to fish that lake at this time of year.
Wouldn't hurt to invest in a handheld GPS too and ask the guide if it's OK to mark a few spots to fish later on your own - I suggest it to my clients if they have their own boat.