It's a bright blue box behind the glove compartment. Open your glove box and push inward on the two sides where the rubber stops are. It will continue to fall forward (you will want to empty out any contents first) and you will be able to see behind it. You should see only one bright blue object there. That's the airbag system diagnostic module.
The exact same part is used in tons of other FoMoCo cars with dual airbags around the same era. Taurus, Sable and Thunderbird for sure, most likely Mustang, Continental, Crown Vic, etc also. I think it's even the same across Gen1 and Gen2 airbag-equipped Tauruses, so it might not even matter if it's dual or single airbags. If the connector is the same, it will work. You can get one from a junk yard, just make sure that the donor car hasn't fired its airbags, as the thermal fuse usually gets blown during an airbag deployment event.
If you know how to solder, you can replace the thermal fuse in your box, and I have done it successfully. But as you mentioned, make sure to locate the fault that caused the short (the most common cause in my experience is a bad clock spring in the steering wheel) before replacing anything, otherwise you will just have another blown fuse right afterwards.
To replace the thermal fuse itself, you'll obviously need a
new one (Radio Shack part# 270-1322, available at most RS stores that have an electronics components section).
When you open up your airbag module (the blue box), you'll see a small black and white plastic box on the circuit board. Carefully separate the halves of that box, and it will open. Inside you'll see the thermal fuse, most likely it will be burnt looking; that is normal and that means that it did its job. De-solder it from the board and replace it with the one you bought, soldering it to the board in the same place. Then put the black/white plastic box around it, snapping together the halves. Put the board back in the blue box and put the blue box back in the car.
It will make sense once you look at it and read this, trust me.
Good luck!
