Just spent the evening putting a handle binding on an ELB I've retillered. The normal proportions are for the grip to extend 1.5" about the centre line and 3" below. I've kept more or less the same propotions in marking the arrow pass on my bows tillered to work through the handle, someties a bit less maybe 1.25" above centre line. The warbow style of course doesn't have a grip, just a mark where the arrow pass should be.