How to flash Xoom

Flash whatever HW to wifi-only SW build MZ604
Download Android 3.0.2 HWI69 for US Retail (or other stock images from here)
http://forum.xda-developers.com/showthread.php?t=1049485

Put on Fastboot mode: adb reboot-bootloader
Unlock bootloader if not yet: fastboot oem unlock

Then flash Xoom

fastboot flash boot boot.img
fastboot flash system system.img
fastboot flash recovery recovery.img
fastboot flash userdata userdata.img
fastboot erase cache

System will automatic update OTA.
(HWI69 -> HMJ37 -> HTJ85B -> HTK55D -> HTK75D -> IML77 (ICS) -> IMM76 (4.04) -> JRO03H(JB4.1.1))