Need to move to .com painless!

Regional, good positioned domain need to be .com now...

[silverbytes]

Scenario: a good positioned regional domain site (lets asssume domain.com.br) that need to be changed into domain.com

Domain available = ok
What now?

The site ranks good enough and email accounts (.com.br) are gently spreaded...

How do I make the transition without loosing traffic, costumers, users...?
If I buy the domain and just mirror the contents won't be penalized?
A redirect from oldsite.com.br to new .com?
Should I move the contents to .com and parking my old domain .com.br?

Site is actually very Google friendly, don't want to dare with that.

Any expert help please?

Thank you!

[King of Bling]

I would think moving your pages to the .com host and then using 301 'page moved' redirects would suffice.

Anyone else?

[silverbytes]

What about the email? Should I set up every old email account to forward to the same account.com?
Any other suggestion?

[silverbytes]

Talking with the hosting people they say there is an "Add domain" in control panel. So you can have 2 domains with separate ftps.
I could copy the contents to the new .com domain and point with a 301 redirect the traffic from .com.ar old domain to the new .com

But will google like that?
is there any problem with the "added domain"?