Hi Rick,
on a feathering side paddle wheel, for example found on Clyde built paddle steamers, when one of the floats is completely immersed at the deepest point in the water during rotation (the float should be vertical), then there should be approx. one third of the floats height depth of water above the top of the immersed float.
I do have a plan showing this, I will try and find it and post it here.
Clark