how to properly install nvidia 470 drivers on ubuntu 20.04?

I tried to switch to the "nvidia-driver-470" using the "Software & Updates / Additional Drivers" facility, but it always says the packages are not going to be installed.

If I select nvidia-driver-470 with synaptic, it installs all required packages, but there is something weird:
It requires an older kernel 5.4.0-1053-gcp (Google Cloud Platform), while the last one is 5.11.0-38-generic!
If I try to boot on the default option 5.11.0-38-generic, nvidia drivers wont load, and resolution will be 640x480 only!!!
If I try the 5.4.0-1053-gcp kernel (compatible with nvidia 470), it will not boot! It will stop booting when trying to initramfs, and then a few minutes later open busybox console...

Installing the 470 removed several older nvidia packages... good I had a root (and boot) backup made with rsync (https://unix.stackexchange.com/a/626503/30352), so I could quickly directly use the previously working OS copy AND/OR quickly restore it back (what I did).

I saw there are nvidia 470 for 5.11.0-38-generic packages, but I cant install them because
linux-modules-nvidia-470-5.11.0-38-generic requires
nvidia-kernel-common-470 >= 470.74, but the only available package is
nvidia-kernel-common-470 470.63.01-0ubuntu0.20.04.2
and if I download https://launchpad.net/ubuntu/+archive/primary/+files/nvidia-kernel-common-470_470.74-0ubuntu0.20.04.1_amd64.deb,
gdebi-gtk wont enable the install button for it! (I guess it is because mine is apparently 20.04.2 and the package is for 20.04.1)

but there is a report of it being installable:
NVIDIA 470 driver doesn't work after suspending Ubuntu 20.04.3 LTS (yeah, why mine with latest updates is apparently 20.04.2??)

Is 470 unstable? despite the additional drivers says it is "tested"?

I need to upgrade because UE4Editor is crashing with VK_ERROR_INITIALIZATION_FAILED "VkResult=-3" https://answers.unrealengine.com/questions/896820/out-of-memory-bug-running-422x-on-linux-with-vulka.html

I got the same error, currenly and somehow the 470 versión of the nvidia drivers that ubuntu provides does not work with kernel 5.11.0-38, downgrading to 460 drivers fixed the issue.

sudo apt remove '^nvidia'
sudo apt autoremove

Reboot

sudo apt install nvidia-driver-460