Seems like I keep having this problem with an addon vehicle that I keep changing. So I have found a few cars that are perfect for my uses. They're always from very simple packs or standalones where there is NO meta file or carvariations file. When I take the 'sheriff' car and rename it to 'police', then drag it into the latest patchday folder, it looks perfect (pushbars included, etc). But when I start the game, and spawn it in the game, the pushbars are missing. I know I can add the pushbars later from the Trainer Menu but would rather have the car spawn with them instead.
What am I doing wrong by renaming the file?