How to install virtualbox guest additions in virtual box V6

Hello peoples,
when running kali linux in Virtual Box
I have tried various ways of getting my kali linux to go full screen by installing virtualbox guest additions but ever since virtualbox has hit version 6 nothing seems to work. I have checked my repos from the official kali linux page. I have tried apt-get update && apt-get upgrade, apt-get update && apt-get dist-upgrade, apt-get update full-upgrade, as well as running these commands separately. Also have tried
apt-get update
apt-get install -y virtualbox-guest-x11
reboot

Nothing seems to work for getting this full screen. I could grind by using scale mode but this is severely annoying, any tips would be appreciated!

How were you able to install

virtualbox-guest-x11? I used the instructions on the kali site -- see details below:

I just installed Kali Version 4.18
kali-linux-2018.4-amd64 loaded in Oracle Virtualbox version 6.0.r128162 (Qt5.6.2) loaded on Windows 10 Home
loaded on a hp notebook Intel(R) Core(TM)i3-5010U CPU @ 2.10 GHz Installed memory (RAM) 6.00 GB 64-bit OS,
x64 based processor
After sucessfully install of kali linux on Virtualbox
logged in as root
started terminal
followed Kali Linux VirtualBox Guest located https://docs.kali.org/general-use/ka...tual-box-guest
issued apt-get update [new line] Reading package lists... Done
apt-get install -y virtualbox-guest-x11 [new line] Reading package lists... Done then [new line] Building Dependency tree
[new line] Reading state information.... Done [new line] Unable to locate package virtualbox-guest-x11

@joja, you opened another thread about it, check the answer there. Long story short, it is in the repo, you forgot something.

I'm in the same boat as Nooblar_Haxur. Brand new Kali download, brand new Virtualbox install, brand new laptop(!). Login, apt-get update, apt-get upgrade, apt-get install -y virtualbox-guest-x11, reboot, and nothing. No full screen. I'm still poking at it but if anyone can help it'd be great!

EDIT:

My solution?

Use VMWare.

my sources.list has

deb http://http.kali.org/kali kali-rolling main non-free contrib

deb-src http://http.kali.org/kali kali-rolling main non-free contrib

is that along with..

apt-get update && apt-get dist-upgrade

not enough?

so anybody that may still be interested. I found a solution to the full screen problem. This seems to me to be an initial installation issue when installing kali linux. I don't think that I ever had to do this before but I poured through the official installation instructions and when first installing the OS, towards the end of the process there is an option to use a network mirror. After I checked yes to this option and ran everything else the same my Kali installation was able to go full screen immediately, no guest additions necessary. I am not sure if this applies to all of the features in guest additions as this was the only one I was concerned with thus far, but it is certainly working at least for the full screen issue.

I tried but it didn't worked. Please suggest some other technique please.