Here you go...
http://forum.ppcgeeks.com/showthread.php?t=43266
Flash from microSD Card (Thanks to MadlyAlive):
1. Make sure you backup anything that is necessary to your day to day operations! At a minimum, please perform an ActiveSync to Outlook or your Exchange server prior to flashing!
2. Rename the custom ROM NBH file from RUU_Signed.nbh to RAPHIMG.nbh
3. Copy RAPHIMG.nbh to the root of your microSD Card.
4. Hold the Volume Down and Power button simultaneously. While you're still holding those 2 buttons, press the reset button with your stylus.
5. When your Touch Pro tells you to do so, press the power button to begin the flash process. If you do not get the message to press the power button to flash, there is a mistake in the name of the NBH file or you do not have the file at the root of your microSD card.
6. When flashing is complete, perform a soft reset.
Phil