[Ritzy2K]

in that command itself, after updating the vehicle plate...respawn the vehicle at the same spot...and it ll b changed..
id write the whole command but im from phone and lil sleepy -

new v = GetPlayerVehicleID(playerid);

later after setting the vehicles plate
SetVehicleToRespawn(v);

u can save the vehicles coord and spawn it right there... also later maybe
PutPlayerInVehicle(playerid, v);

good luck and good night.