Exchange 2007 setup wizard in mixed DC domain

I have a couple of DC's running 2K still and one of them is an exchange 2K box. MS says that if you are running the RTM version of setup you must specify a DC running 03 as a switch when prepping the domain. I would like to run the setup wizard instead so my question is this... Will the setup wizard ask me about the 03 DC I want to point to or will it find it on its own? I am using my select disks and they are not SP1.

Confused.

Thanks