How to inject drivers in the Windows 10 upgrade task sequence

Hello There,

I used this article (https://technet.microsoft.com/en-us/library/mt426642(v=vs.85).aspx) and created a Windows 10 upgrade task sequence. This works perfectly fine, but the only issue is that I cannot inject driver packages to this task sequence. I have a few flavour of Lenovo laptops with different driver models. 

Windows 10 installs most of the drivers during the upgrade, but some of the video drivers are not installing since they are not in the Windows package. Please advise if you have any suggestions that may help in my situation. 

Thanks,
Sameer