[GTALUG] VirtualBox Guest Additions in Ubuntu VM doesn't work

Question for Ubuntu users... VirtualBox Guest Additions installed by default on Ubuntu/Kubuntu VM is 5.0.18, ie. modinfo vboxsf Now, when I try to upgrade to latest 5.1.8, the install script (VBoxLinuxAdditions.run inside VBoxGuestAdditions.iso) finishes OK, but the version is still 5.0.18. Looking at kernel drivers, it seems that I have 2 versions of drivers: kernel/ubuntu/vbox/... --> from Ubuntu kernel misc/... --> newly compiled When I removed the default kernel drivers, then it uses the newly compiled 5.1.8 drivers. (which is what I want) What is Ubuntu-way of removing kernel drivers, or specifying which driver should be loaded? -- William