you will need to do a new alignment after you put new tie rod ends on it. You can do a good job of estimating where it should be though. Count the threads on the old tie rod end from end of sleeve outward and screw in new end same amount.
Try measuring from inner tie rod to outer end of the old tie rod end prior to removal.
There is also a way to do an "approximate" alignment yourself with string and measuring the center of tires etc...I've never done that though because i love my tires too much to have them wear prematurely.
Anyone watching the Orange Bowl in a couple of weeks? Va Tech playing some other team (I forget who) but the QB all year for Tech has a first name of Tie Rod. No joking, really. Tyrod Taylor. I have joked all year long that he must have a brother named shock absorber. Parents now a days are either really mean, or just plain ignant.