Changing Welcome Screen on ic502 Sprint

I need help on how to replace the current welcome screen as well as the shut down screen on my ic502. I have just started to reconfigure my phone using phone Tools but can't seem to find where the setting is in the phone. Already have the screens (animated gifs) that I will use.
It is with sprint / Nextel screen and Moto screen for the off.
Any help would be appreciated.

Thanks in advance.

Most Nextels settings are in the menue> settings> display> wallpaper...
you can also use your own gifs, just rename them same as the default ones.

(See my sticky on stock wallpaper)