Does anyone know where in the ini files I can change the air ambulance model that spawns when using the Bejoljo plugins? I've looked through them multiple times but can't seem to find the line where I can change it 

Go to GTA V/plugins/lspdfr/UltimateBackup and open the SpecialUnits.xml file.

Search for the following lines:
 

<SpecialUnit name="Air Ambulance" role="medic" code2="False" code3="True" pursuit="False" traffic_stop="False" felony_stop="False">
		<LosSantosCity>
			<VehicleSet spawn_distance="200">
				<Vehicles>
					<Vehicle livery="2">POLMAV</Vehicle>
				</Vehicles>
				<Peds>
					<Ped>S_M_M_PARAMEDIC_01</Ped>
				</Peds>
			</VehicleSet>
		</LosSantosCity>
  		...

 

If you want to change the vehicle model for this unit, change the model name from "POLMAV" to something else in the following line:
<Vehicle livery="2">POLMAV</Vehicle>

Don't forget to change it for the other regions, too. What I described above would only change the vehicle model for "Los Santos City".

I hope this was understandable. Let me know if you have questions.