@Raval So, you want more than just a few addon vehicles while using F7YO's gameconfig, is that correct?
If that is the case, I would suggest you look into the combination of dlc's.
Here is a link to show you how to do that.
Just so you know, this will not replace any vehicles and only add them on. So only you will be driving them, and they won't be flying around in the sky by ai, or driving around by ai.