2badazzstangs:
Sorry to hear about the new gear getting chewed up. Here's the poop: 23-teeth mean the blade of each tooth is thin (so, easy to damage). I recall that my stock VSS gear is orange but it is for an auto with 3.08's. I *think* it has 18 teeth. The teeth are thicker and stand up to wear much better thann the white gear. Only thing that I suggest is to ask your local Ford Parts guy for a stock VSS gear for an auto with 3.08's and you will get a stout little VSS gear.
edit
In fact, the orange gear has 20 teeth. There are other VSS gears that have 19, 18, ... gears but I don't have my ancient FRPP catalog handy to tell you what they are (sorry).
end of edit
Once you get the SpeedCal, you have to fish the SpeedCal harness up into the cabin. for me, I brought the harness up at 12 o'clock and the S/C sits between two plastic buttresses on the inside of the console - nice and snug and it doesn't rattle around. You can always use a strip of Velcro to hold the S/C box in place if your console is different than mine.
Calibrating the S/C is easy. Start with the settings that you get from Dallas Mustang (they give you a table in the instructions) and then you can use milemarkers, a stopwatch (operated by your co-pilot), and about 3.0 miles of steady speed at 60 or 65 mph on a flat stretch of highway. Then, calculate the true speed and compare it to the indicated speed on the speedo. Adjust DIP switches accorrdingly. It takes a little trial and error but you can eventually get the speedo/odo error down to less than 1%. Of course, if you have a GPS unit then you don't need the stopwatch & co-pilot. Just run for 3.0 miles at steady speed and see how things look.
Phew, that's a lot of typing. Keep us updated, please.
Chris