[wiswind]

I would go to a FORD dealership parts department.
Have your VIN, and they should be able to help you.
Mid-year changes can bite you, and the VIN should cover that on their computer.
They have a really good parts look-up system on their computers.
They have pictorial break downs that get right down to the part(s) involved.
I have not seen anything that comes close to the detail that they have.
Paying list price for the speed sensor will be cheaper than trying to battle with it on your own.
It sounds like you have reached over $100 of frustration factor already (I do put a price on that).

I remember a post on a FORD forum where a FORD technician recommended replacing the speed sensor with a genuine Motorcraft sensor because the Motorcraft sensor came with a new gear.
Make sure that you get the gear and sensor when you buy one.

I am only familiar with the '96, and it has BOTH the Vehicle Speed Sensor (VSS) that is located on the back side of the transaxle......at mid point.
It is hard to get at to change due to all the things that are in the way.
Otherwise, it would be simple to change.
I think that Alldatadiy has it listed as OSS at some point also...as well as VSS.....but it would be the same measurement.
If they moved things around, the breakdown at the FORD dealership will show it for your vehicle.

The other sensor is the Turbine Speed Sensor (TSS), which is located on the driver's side end of the transaxle.
This sensor measures the speed of the shaft that comes out of the torque converter, but before the gear ratios of the 4 speeds.
The PCM knows the speed into the torque conveter from the engine RPMs, and the TSS tells the PCM how much slip there is in the torque conveter.
This is a value that helps the PCM control the transmission, but not useful in determination of the vehicle speed.

But then, asking you to return the transmission so that they can install the sensor?......who is paying the shipping charges?
One would think that they could put the sensor in a little box and send it to you......FEDEX overnight would be a small fraction of the cost.