Don't know if this is the official "correct way" but it works for me on all kinds of cars... er, most anyways.
To get the old ones out, make sure they are clear of the hub and give them a few good bangs with a hammer until they pop out. To get the new ones in, I put a nut that is going to take up some space so the lugnut doesn't bottom out, then tighten slowly with an impact gun until the stud is almost fully pressed in. Finish once the wheel is on.
Might also be better if you pulled the axles and did what Zooed Plus said, but also hitting the backside of the studs with a hammer to "help" them seat in the flange.I've stripped new ones just using an impact alone. Also a good time to check the axle bearings and seals if they've never been changed.
From one who has done it the redneck way and
bent the flange.
I would pull the axle out to be safe and use a press or a vice to support the flange while you knock out the old studs.
You can use an impact to reinstall them and aline the splines on the stud with the prev spot easier when you can see it and manuver the axle to work on.
PB
Just a fore warning a bent flange makes one heck of a vibration.