Installing android playstore on a "custom" pad

My problem  :

• I have a pad with custom OS, based on android 4.2.2
• I do not have th play store installed 
• I want one ! :-)

Disclaimer

WARNING all this post constains informations that works for me.

• I download and do many things that could be risky...
• I don't know if my donwload are safe or not 
• I don't know if the command line I does will work and if they are safe (probably not cause I change credentials on /system....)

So if you reproduce this "receip" be aware that's at your own risk!
At least does a back up and save all your things... (if it's not done regularly)

The target

Install some file (apk) in /system/app :

• GoogleServicesFramework.apk
• OneTimeInitializer.apk
• GoogleLoginService.apk
• GoogleFeedback.apk
• Phonesky.apk

Get those files

I download a zip for gapp (google application), it 's name like :gapps-jb-20130812-signed.   
I Download this one cause it's for the android 4.2.2 (the one that is serving for my device customization ).
Download those file as "pack", give me a coherent files association (compatible).
So, unzip then search the desired files, we will use them after adb install.

Install adb

ADB is an acronym for Android Driver Bridge : this piece of software allos you to take control of your device from you PC.

I  download  a file adb-setup-1.4.3
see http://forum.xda-developers.com/showthread.php?p=48915118#post48915118
for more explanation.

I try first to install "adb driver" but with win10 I had  problem with peripheral installation because the system (win 10)  enables driver signature enforcement by default. I try this but finally install " adb-setup"

Push those file

WARNING : see disclaimer chapter.
push each file using this adb comman line :

adb push GoogleServicesFramework.apk /system/app

repeat this for all files. Previously I transfer those apk to the device then click on each and try to install , but this not  work (GoogleServicesFramework.apk does not install at all...)
If you have a fail due to Read-only file system you have to :
use adb shell in a win10 administrator command line tool :
adb shell
then you have adb sheel (#)
# su
# mount -o,rw remount /system/app

At the end

I restart my device and all is working. I can now have access to android store.