Rich,
Over the years most of my “Mustang” purchases have been from either Tony Branda or Virginia Mustang. All you need is a turn signal switch. The switch comes without the connector. Normally your old connector is in good shape. Is yours totally unserviceable? Burned and melted? They come without the connector because you have to feed the wires down the column to install the switch and the connector won’t fit. In fact it takes a bit of patience to get just the wires down the column!!
The “switch” side of the old connector is designed with “snap and lock” pins. When you get the new switch, examine the pins and you will see the “lock” tabs. You must lay on the front floor, with the connector apart, and carefully insert either a straight pin or a small diameter (just will slip over the pin) piece of tubing (steel or something rigid) over the pin to allow it to pull free. I take the driver seat out these days when I dive under the dash. Four nuts and a lot more comfort for my old body. The car side of the connector still has the pins in their proper placement. (VERY IMPORTANT) When you pull the old switch out, tie a string or piece of wire to it so you have something to help you pull the new wires down the column. The path to drag them down is so tight you have to stagger the pins in order to keep the “lump” of pins as small as possible when you drag them down. Lots of patience and gentle pulling. Just replaced mine in my GT/CS a year ago. Second time since I have owned it!!! We drive it a lot!!
Once all wires and pins are down they snap gentle in place in the old connector. The “car” side of the connector has the proper order. You will find the colors to be older and sometimes not a true match. Enough of them are that you can figure the odd ones out.
I am going to go downstairs in my shop. I may have an old connector lying around (many years of Mustanging). Even if yours has a burn mark or two as long as it is not totally melted it is ok.
Of note, any 67 to 70ish Ford or Mercury car or Ford truck normally has the same connector. Snip snip, in your pocket and out you go. In the Northwest we still have a few old cars laying around in the wrecking yards.
Rob