To mitigate that Android X86 does not have a recovery boot mode, where you can install update packages, I found an alternative way.
I have tested with Android 6 image. To do this I used Flashify app. First of all is mandatory to install Super Su app.
Once you run flashify, you give permanent root privileges. Then you are be able to Select the zip file where is the zip update package you want to install and then tell flashify that uses cwm, update works perfect, then you have to restart.
Android 6 play store does not work (Error 963).
I tested it with flashing the Android 6 x86 opengapps. (but without success to avoid 963 error)
I hope this idea will be helpful
Cheers