What is the correct mounting hole placement for the side view mirrors on a 66 Mustang. I have a new replacement door on the drivers side that has pre-punched holes, the front hole is 3.5 inches from the front of the door. I've seen the mirrors in both a front placement, like these holes are, and back further, a little past the vent window. Which is correct, and if mine are not correct, what is the correct front hole measurement?