OS is quite dense, around .75 , I think. with only 60 inches to work with, you'll have to make it bend thru the handle. How far does the split go? if you can cut off the split portion of the limb and still have enough for a bow, do it. what is your draw length and desired poundage? basically remove the bark carefully and then leave the back alone... reduce the belly during tillering, leaving it full width and keeping the belly flat. Narrow the tips for the last 8 inches or so. In the end, the limbs will have a cross section like a half circle. The handle will likely be a little thicker than half the diameter of the piece (the handle will contain the pith). How long has it seasoned? Beware of further drying cracks on the ends.