I did the same as sonimuts describes but could not get the sim card to work afterward. PaulOBrien, can you make another rom based on 570 firmware? If not, I recommend removing this page as it is pretty pointless to post a rom and not provide a way for people to install it who have newer firmware. You made me waste two days of my time. The 506 firmware from Huawei does not work. It's the same file which is linked to many places. The source is Huawei, and it does not work. The link provided by sonimuts is for a corrupted file, and the same file is linked to all over the internet. I have tried searching for other 506 firmware versions with http://forum.xda-developers.com/tools/general/huawei-firmware-finder-team-mt-t3469146 but none of them were available. So, Mr Brien, please recommend how we can install the old 506 firmware, or how would you suggest that we use the rom?