The threaded shank on tie rod ends is not always the same length, depending on manufacturer, so counting threads does not assure proper previous toe alignment.
If you measure from the center of the lower rod cup washer to an indexed line on the rod [ that you mark] , you can get the exact previous measurement..but then again, that only brings you to the previous alignment, which you are assuming was correct.
Toe measure/alignment is the correct way to go .