Making new domain name primary URL

Hello –

First – yes I have searched forum posts and consulted the Codex, but this situation seems to be a little different than what I am reading about and just want to be 100% sure I do this the right way.

Client has a website hosted at Blue Host, we’ll call it xyzonline.com. It’s the primary domain on the account. Client also has xyz.com, xyz.biz, and xyz.net registered and assigned in Blue Host as parked domains pointing to xyzonline.com. Therefore, no matter which URL you type in, you see the website hosted at xyzonline.com.

Client now wants site visitors to see xyz.com in the address bar no matter which of the domain names site visitor uses to get to the site. So if they type xyz.net, he wants the URL to change to xyz.com.

Questions:

1. Is this possible, considering that xyzonline.com is the PRIMARY domain on the Blue Host account? Is it possible for xyzonline.com to show xyz.com in the address bar?

2. Do I simply go into my WordPress settings and change the WordPress URL and site URLs from xyzonline.com to xyz.com? Is there more involved than that? I’ve read the “changing your domain name” articles in the Codex, is that the process?

I’ve moved sites before, and I’ve changed site URLs before, but have never tried changing a primary domain and masking the URLs. (and of course in the past I was doing it on non-live sites – this is a popular local site that is up live through this.)

Appreciate any help, thanks!