Car goes to patchday9ng's vehicles.rpf. There is not a police4 in there, you add it in and it will load itself.

Visualsettings.dat goes to; update/update.rpf/common/data


Add this into the carvariations.meta located in; update/x64/dlcpacks/mpchristmas2/dlc.rpf/common/data

<Item>
      <modelName>police4</modelName>
      <colors>
        <Item>
          <indices content="char_array">
            134 
            134 
            156  
            156 
          </indices>
          <liveries>
            <Item value="true" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
          </liveries>
        </Item>
        <Item>
          <indices content="char_array">
            134 
            134 
            156  
            156 
          </indices>
          <liveries>
            <Item value="false" />
            <Item value="true" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
          </liveries>
        </Item>
        <Item>
          <indices content="char_array">
            134 
            134 
            156  
            156 
          </indices>
          <liveries>
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
            <Item value="true" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
          </liveries>
        </Item>
        <Item>
          <indices content="char_array">
            134 
            134 
            156  
            156 
          </indices>
          <liveries>
            <Item value="false" />
            <Item value="false" />
            <Item value="true" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
          </liveries>
        </Item>
        <Item>
          <indices content="char_array">
            134
            134
            156  
            156 
          </indices>
          <liveries>
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
            <Item value="true" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
            <Item value="false" />
          </liveries>
        </Item>
      </colors>
      <kits> 
        <Item>157_massacaro2_modkit</Item>
      </kits>
      <windowsWithExposedEdges />
      <plateProbabilities>
        <Probabilities />
      </plateProbabilities>
      <lightSettings value="2" />
      <sirenSettings value="13" />
    </Item>
