Wheel studs are a press fit. Getting them out requires either taking off the entire hub and pressing them out or brute force that could break other parts. Getting them in is not as hard. If you are able to get them out on the car you can just use a nut and good breaker bar to tighten the wheel stud into place. If you have the hub out, then just press them back into place. I personally would do it right, take the hub off, press the studs out, press the shorter ones in, and install.