CarmelaLemoShiba

it works now, thank you very much

From what I can tell this is Kane's FPIU base, please look in the YTD for a texture name fpiu_sign_# (1 or whatever). 

My guess is that Scorpian is using shared textures between his vehicles which is why some other textures are missing.

Take a look to see if the fpiu_sign_1 file is there though first and check in with me.
 
After a closer look I feel that some of your normal maps aren't showing up and they could be using the BC7 compression which is only supported on DX11, make sure your game's setting is on DirectX 11 or higher.
The liveries and other textures are there upon downloading for me. Upon checking, the livery and lightbar are using BC7 compression and your game not being on DirectX 11 or higher will make it not show, I am 100% certain this is the issue.

Hey! So ik this is now almost a decade after the question, BUT I may have found the answer on Canva or something close to it!
 
The font I found is called Acuity and it looks like this

More like this if you lower the spacing of the top letters to -82

Recently I added the Grapessed Police Department, Sandy Shores Police Department, and the Paleto Bay Police Department. Whenever I go to call for Code 2 or Code 3 local backup, nobody shows up ONLY from the GSPD, and the SSPD only shows up in certain areas of Sandy Shores; Paleto Bay PD works fine as they spawn anywhere in Paleto. 
I set up the GSPD to only patrol: <Zone>GRAPES</Zones>
meanwhile I set up SSPD to patrol: <Zone>SANDY</Zone> <Zone>DESRT</Zone> and <Zone>HARMO</Zone>
 
Other units that have more than one region set to them work (*i.e. the LSSD patrolling Davis, Chamberlain Hills, and Strawberry.
 
Idk what the issue could be because it resembles any other Custom Backup
 
Screenshot of the units: