The lettering is busted because the mod is slightly outdated. It still works and functions, just remove the lettering off the hood.
I got the letters working again by copying over 3 .dds-files from an older version of the game I still have on another computer. The 3 files that can't be loaded are: barstow_lettering_d.dds barstow_lettering_n.dds barstow_lettering_s.dds from the barstow.zip in the game files. If you look in the game files from 0.37, these .dds-files don't exist anymore in the form this mod needs. If it is allowed for me to upload the 3 missing files here, I would do so. They just need to be copied to the following folder in your user account folder in Windows: 'AppData\Local\BeamNG\BeamNG.drive\current\vehicles\barstow' (the 'vehicles' and then 'barstow' folders in 'current' probably don't exist yet, so just create them).
Got bored, I decided to use the method that @GavrilMan2973 (Huge thank you to him for letting me use it!) used to update the lights on the Functional AR162B H-Series Addon mod to refresh this thing a bit. I updated the headlights and blinker signals using their method but decided to update some more lights and other stuff afterwards in an attempt to experiment with the smooth lighting feature that was added a few updates back. Changes: Used @GavrilMan2973 's method to update the blinker signals and headlights, Added smooth lighting to many lights (Will leave a full list of as many I can remember in a spoiler at the bottom of this list), Fixed the red left lightbar being mapped to the pickup trucks body (How this happened in the first place I have no idea), Changed the 'SPOTLIGHT' parameter in the lightbars to 'POINTLIGHT' so they are visible from the rear of the vehicle, Edited some glowmap brightness's, Edited the reverse light texture UV to make it fit a bit better, Maybe some more stuff I can't remember, Spoiler: List of lights currently with smooth lighting Normal Oldstyle headlights (@GavrilMan2973 method), Police Oldstyle headlights (@GavrilMan2973 method), Blinker signals (@GavrilMan2973 method), Normal Oldstyle taillights, Oldstyle gauges, Rotatable police spotlights, Flatbed side taillights, "Sideflare" (I think that's what their called?) side taillights, Maybe some more I can't remember, Again huge thank you to @GavrilMan2973 for letting me use his method! Enjoy More updates might happen in the future This file is based off of the file found on the first post.Seriously though how does a lightbar material get mapped to a pickup truck