Android-13 for vim3

Which Khadas SBC do you use?

VIM3

Which system do you use? Android, Ubuntu, OOWOW or others?

Android-13

Which version of system do you use? Khadas official images, self built images, or others?

Self built image of Android-13

Please describe your issue below:

I bought a vim3 board via this page introducing, Using Reference Boards  |  Android Open Source Project , it provided a user guide how to build an image in previous page, but now, it only redirect a link to your home page.
Before I followed previous page instructions, but it can’t build with a self built kernel.

Could you please provide a guide where to download your full source like uboot, kernel with android-13 and also provide a guide how to build a self build uboot, kernel, and aosp-13?