How do you remove and replace the upper control.

You need a special bushing press to force the old ones out and the new ones in. It's important the life of the new ones that you don't tighten the bolts until the truck is sitting on the tires at normal ride height. If you tighten them when the truck is jacked up and the suspension is hanging, that will put them in a permanent twist when you set it down. You'll need an alignment too when you're done.