3" to 7" work well in Indiana. Lots of saddle hackle, EP Fiber, and holographic flash. Deer hair makes great heads and use the biggest eyes you can fit onto the fly. Gamakatsu G10S hooks 3/0 to 6/0 work great as well as some of the large Gamakatsu catfish hooks. If you want articulated flies use 40# steel leader wire to connect the parts. Also, Use gel spun thread and plenty of cement.
Good luck and have some fun with this. Be creative with the use of material. There are plenty of videos on tying pike flies. Hint, big browns will also eat these things.
Jery