Re: old as dirt
Sure, Those older motors were set to work with the old Merc Tachs. if you want to use a newer aftermarket tach, remove the wrap cowl, and move the (non distributor) brown wire from the switchbox to the rectifier. Connect the brown wire to either of the yellow stator wires. Now the tach plugs into the front of the MerControl box, using the three prong plastic connector.