As a general rule for older designs, 15% mean aerodynamic chord is a good starting point. On your Banshee measure the total chord, flaps and all, halfway out the wing, and figure 15% back from the leading edge. I suspect that is forward of where the plans show. A Twister balanced thusly flies very nicely. I like to say, "A nose-heavy airplane can be retrimmed; but you may not be able to repair a tail-heavy airplane."