Use exactly same Gitlab windows image used by shared gitlab-runner on my own gitlab-runner

Use same Gitlab windows image used by shared gitlab-runner on my own machine

Hello,
I designed all my CI/CD with Windows shared gitlab-runner but I would like to use my own machine now and don’t change the ‘base docker image’ (and default software installed on it).

As I understand:

What I don’t understand is that when I use one image on my own machine (gitlab/gitlab-runner-helper:x86_64-e95f89a0-servercore1909 for example), it doesn’t work the same way as with a shared runner: I can’t use ‘choco’ for example while it should be on the base image

Result on shared runner (without specifying any image):

Running with gitlab-runner 13.4.1 (e95f89a0) <-- No indication of the EXACT docker image used
[0K  on windows-shared-runners-manager Hs8mheX5

(...)

choco install git -y -params '"/GitAndUnixToolsOnPath"'
Chocolatey v0.10.15
Installing the following packages:

Result on my machine (by specifying ‘gitlab/gitlab-runner-helper:x86_64-e95f89a0-servercore1909’ as docker image):

Preparing the "docker-windows" executor
Using Docker executor with image gitlab/gitlab-runner-helper:x86_64-e95f89a0-servercore1909 ...
Pulling docker image gitlab/gitlab-runner-helper:x86_64-e95f89a0-servercore1909 ...
Using docker image sha256:26e513d1b0131ab343f3ded5e96179e776dfe0637479ffdffa6f1f85ba1d63e3 for gitlab/gitlab-runner-helper:x86_64-e95f89a0-servercore1909 with digest gitlab/gitlab-runner-helper@sha256:33985c4da6827963eda1e2b9aa3e33b43934adbb9e26b497a015aa2a3dd827bb ...

(...)

$ choco install git -y -params '"/GitAndUnixToolsOnPath"'
choco : The term 'choco' is not recognized as the name of a cmdlet, function, 

Thanks in advance for your help
Quentin

Update: The image seems to be compiled from this script: .gitlab/ci/container-image.gitlab-ci.yml · master · GitLab.com / GitLab Infrastructure Team / ci-infrastructure-windows · GitLab or this script .gitlab/ci/build.gitlab-ci.yml · master · GitLab.org / CI-CD / shared-runners / images / gcp / windows-containers · GitLab

It uses Google cloud own registry which is maybe private ?

I created a ticket on the repo: Allow anyone to access your build Windows docker images (#1) · Issues · GitLab.com / GitLab Infrastructure Team / ci-infrastructure-windows · GitLab