For anyone who wanted to use the other add-on vehicles as replacements, I was able to get it to work by just replacing carcols and carvariations, then changing the siren settings (I used LiveLights, but if you can't be bothered: id 15 is NYPD Vision SLR, 16 is NYPD Vision 2nd- and 3rd- Generation, 17 is NYPD Vision 1st- Gen)