Well, technically, assuming that the old and new ball joint are manufactured perfectly concentric, you would be good to go. I would change them, and if it doesn't pull to either side on a test drive, call it done.
-Rouphis
I have a 1996 F150 with a 4R70W, and here is a cut/paste from the owners manual:
If your vehicle is equipped with an Electronic 4-Speed Automatic (E4OD or 4R70W) transmission, operate in Overdrive. Refer to the automatic transmission operation earlier in this chapter.
When descending a steep...
You will be fine either way. I personally prefer g05 but all three will be equally fine in that application. Also, that is not solely an import motor. Ford used it in the escorts.
-Rouphis
In miatas the TB is due at 100k and its a non interference engine.
Its rather easy as far as TB's go. I changed my miata's timing belt @ 192k and it was original.
Hope this helps.
-Rouphis