Welcome!
You can find police and fire vehicle parts for use on GTA: San Andreas mods here.
Any parts with "OPD Mapped" in the file name only uses the "OPD_Stuff" texture (and the vehiclelights128(on) in the vehicle.txd).
Any parts with "OPD Mapped" in the file name only uses the "OPD_Stuff" texture (and the vehiclelights128(on) in the vehicle.txd).