*** YOU NEED TO REGISTER ON THE FORUM BEFORE YOU CAN ACCESS THE DOWNLOAD LINK ***
INSTALLATION INSTRUCTIONS
http://www.xperiablog.net/2015/03/17/guide-to-installing-xperia-lollipop-using-xperifirm-and-flashtool/
- Open link above and skip to the section entitled “FlashTool steps”.
- As you have already downloaded the FTF firmware file, skip to the section where you need to “Flash device”.
XPERIA FIRMWARE DETAILS
This is official stock Sony Xperia firmware.
Model: Sony Xperia Tablet Z LTE (SGP321)
Firmware version: 10.7.A.0.222_R1E
Region: Singapore (Generic) [1273-0364]
Android version: 5.1.1

Xperia Tablet Z LTE_SGP321_10.7.A.0.222_Singapore_Generic 5.1.1
Sony Xperia Tablet Z LTE (SGP321) Android 5.1.1 firmware - Generic Singapore