Android 7.1 (Pinebook)

[Wizzard]

If I understand it, when I want to install it to emmc, I just have to grab the installer file from ubuntu img, modify it, copy it to sdcard with A7.1, boot it and run that script?

Yes. Delete the ubuntu image on the installer and rename the A7.1 image to whatever the ubuntu image is called (IIRC its Pinebook.img).

So this is just opposite of what I said so I have to use ubuntu emmc installer image on sd and replace one file on that sdcard from A7.1.

1) Flash the ubuntu install image to SD
2) mount rootfs of the installer 
3) delete the pinebook.img (please check, I cant remember if thats what its called)
4) rename A7.1 image to 'pinbook.img' 
5) copy the renamed A7.1 image to the installers rootfs
6) put the SD into your Pinebook

Now it seems very clearly, thank you very much, I will try it today, hopefully.