Thanks Dan. The second diagram from the 55-59 FAM appears to say i can use the visor mount as a fixture to set the drilling points for the three screws rather than a template used in the first set of drawings. Actually that was my plan. I just needed confirmation that the dimple was the starting point.
Actually I don't need an inch and a half hole either, a one inch hole (which i have a drill the right size) will work fine for the visor mount I have.


1956 3100 three speed 6 cyl. Stock with a few upgrades.