My father and my sister both own a Taurus, and being the family wrench, I HAD to learn about them...
As far as doing an Auto-Rx, if the ATF has only been changed once in 160,000 miles (as you mentioned above), then I don't know if that's a good idea...I don't have any experience with ARx in a transmission, especially not one with that many miles on it. I'm sure there are others here who will chime in.
The Taurus is a great car...it really has only 2 problems: Head gaskets in the 3.8L and the transaxle in all of them...normally, I recommend changing the ATF every 25,000 miles at most...more often if you tow or haul heavy stuff around, or if you drive in a "spirited" fashion.
Kestas suggest doing a complete fluid exchange; it the ATF is red and clear, then that's an excellent idea. However, if it's brown and smelly, you should start saving for a rebuild. Changing the the fluid slowly, by doing a pan-drop and filter now, then doing a pan-drop again after a couple of thousand miles, then perhaps a third pan-drop after a couple thousand more, may help extend the life of your transaxle.
My wife spent summers at her grandfather's house on 2nd Ave in Scituate...if you'd like, I could come by and give you a hand...send me a PM with your address.