I found some cars way to clean after 200 years of radiated rain and dogs pissing on them, so i made them look more rusty. 2k and 1k textures. You can mix them.

Installation

1- Edit  Fallout4Custom.ini  in MyDocuments/MyGames/Fallout4 and add the following lines:

[Archive]
bInvalidateOlderFiles=1
sResourceDataDirsFinal=


2- extract the files into your game /Data folder

Or use NMM.