Have been reading alot abt how to debrand SE Phones like my "3" logo K800i. Because the branded firmware, I did not able to upgrade the firmware by SEUS. So Decided to give it a try myself.......
Some useful hints :1)Fully charge your phone using wall charger
2)Do not USB hub - plug the phone straight to the USB port on your PC's motherboard
3)Make sure you set plenty of time for doing this
4)Remove SIM Card and Memory Card from the phone

Abit worry, I killed one of my phones few years ago while i was flashing my panasonic GD88 because of PC crashed~ Ok start PhoneXS~
曾經因為自己不小心flash我的 Panasonic GD88而弄坏了...所以有一點担心.
廢話不多說, 打開 PhoneXS
Select USB cable ~
選擇 USB
Select the right Firmware (MAIN) , FS, and Custom Pack, and Start~
選擇适合的軟体, FS, Custom Pack, 然后可以開始~

Click FLASH~

start from 11.20am~ let's see how many hrs do i need ~
早上十一多開始. 看看需要几个小時~
waiting... 等待着...
waiting... 等待着...
Still waiting ... 還在等待着...
Yes Finished Brute force. It took abt three hrs~ Done!!
Yahooooo!! 終于完成了! 差不多整3个小時!

Still abit worry after unplugged the phone, have to wait til i start the phone only know the result~
YESSSSSSSSSSSSSS還是有一點担心. 因為還沒打開手機! 不知道能不能開~ YESSSSSSSSSSSS

WELL DONE~ Local Firmware interface~
成功了!!!
R1ED001 firmware~
軟体 R1ED001 The most important is to read , read, and read~ from the following website!!
And I wanna thanks the moderator of SE-NSE "Lemming"! Yes Thanks you very much for sharing all the information.