Verify first.....

Ill add that, I've done many alignments to street cars, and we never did anything other than set the car up, check for worn suspension parts, check tires and tire pressure, perform caster sweep, then make adjustments. We never for example put 200 pound of weight in the driver's seat. I have heard of doing it though and I seem to recall it's for road racers, Trans Am guys etc. That are in competition. I suppose if you are going for precision it couldn't hurt. But I I will agree it's unnecessary in an everyday car.