Thanks Doug. Three replies to one question! Very helpful replies - issues I hadn't considered as I was thinking about mounting the vise slightly further in (to the right) than yours to avoid a leg, retaining a short piece of bench top at its original depth to the left of the vise. That might not be such a good idea, or even possible, to allow the hinge pin to slide in without making an excessive width notch. Food for thought. Maybe adding a 2 17/32" skirt to the front of the existing solid skirtless top would be an easier solution. Bench restoration is scheduled to start next Monday!
Mark