I went to a local yard (Ecology here in CA), pulled a speedo out of a similar year t-turd, dissected the assembly, pulled the entire gearset and motor (just in case), showed the cashier, walked out only paying for my entrance fee of $2.00.
By dissecting the donor car's speedo I was able to take some mental notes & repeated the process on the speedo in my car. Just be sure to grab the speedo needle off of the donor car in case you happen to mung up yours. I used two flatblade screwdrivers to remove the needle, some recommend using a fork. I set it back to whithin its own width at zero, but I think it reads off by 1 or 2 mph (as per my Garmin 295).
Took about 1/2 hr to swap the gear & is a no-brainer save for getting the black fascia off from around the steering column. OD works fine...
You may have a hit and miss situation with the gear (some are cracked or broken), but I was sure to inspect the replacement gear to be sure that is was not discolored (which is a sign of stress in ABS). This gear (and the assy) is very common among t-bird and lincoln speedos, so you will have no shortage of donor cars. Also be SURE to clean out the gears in the outer drive. You'll see little pieces of your old gear in there. I used a 90 degree scribe, but anything with a sharp point will work.
I would forgo paying $25.00 for a replacement gear. It's like their selling Cessna parts or something. Gimme a break.
M Randolph