In the dash, on the passenger side.
On a 1996 Ford Bronco the turn signal flasher is plugged in to the fuse box
under the bonnet
Above the left knee
On a 1996 Ford Aerostar : The fuse box is under the instrument panel , on the drivers side
See http://www.analogstereo.com/ford_aerostar_owners_manual.htm
Under the dash on the drivers side
There is a large round chrome fuse called "The Flasher Unit". It is located next to or close by the fuse box down by the drivers feet, or there might be a fuse in the fuse box,the fuse box is labeled.
A fuse box diagram for a 1996 Ford Thunderbird LX can be found in a Chilton's automobile repair manual. This type of manual can be found at some libraries and most automobile parts stores.
Open the drivers door , and IN the drivers end of the dash you will see a removable plastic fuse panel cover ( the fuses are behind the cover ) on your 1996 Ford Ranger
Under the instrument panel on the driver side
On a 1996 Ford Windstar : Under the dash on the drivers side , not too far from the inside hood release
#21 in the fuse panel under the driver side dash.