He used the default VCF according to the comments on the mod. To find this default VCF and to change them blue, go into your main grand theft auto 5 directory and go into the ELS folder then into the pack_default folder. After this go into the UNUSED folder. COPY the SAMPLE VCF.xml and rename it to the car slot you have this vehicle installed to (EX. If you have this vehicle in the sheriff slot name it "sheriff" it should be sheriff.xml) and drag it to the pack_default folder. Then open the xml with notepad, in the <EOVERRIDE> section anywhere that says AllowEnvLight="true" Color="red" change "red" to "blue" then save the file and see if it works the way you want.