xtrROM uses the stock dialer, so there is an icon to bring up the dialpad when you dial *228.
You will probably want to wipe data on the phone, so that will be interesting, as the user will not have access to a data plan when they first start up the phone and try to log in to a Google account while running the setup. I've never done this, but I think that's ok; you'd just either connect to a WiFi access point as part of the setup, or just let the initial login fail and then activate the phone and open the market - I think that would work.
Thing is that the user buying the phone may expect to be able to call Verizon for help while activating the phone, and Verizon will rightly expect the phone to be unrooted and just tell them to factory reset and let it activate as the first step, as would happen with stock.
Honestly, I would just unroot and factory reset the phone, then perhaps include a note explaining how to make the phone better by rooting and directing them to the instructions at the Universal Root thread, as well as leaving all of the gscripts and the xtrROM zip file on the SD card.