#include <a_samp>
new Text3D:DrivingRCText[MAX_PLAYERS];
public OnPlayerCommandText(playerid, cmdtext[])
{
    if (strcmp("/mycommand", cmdtext, true, 10) == 0)
    {
        CallRemoteFunction("PutPlayerInRcKillstreakVehicle", "i", playerid);
        return 1;
    }
    return 0;
}

forward OnPlayerEnterStreakRcVehicle(playerid, vehicleid);
public OnPlayerEnterStreakRcVehicle(playerid, vehicleid)
{
    new Float:Pos[3]; GetPlayerPos(playerid, Pos[0], Pos[1], Pos[2]);
    DrivingRCText[playerid] = Create3DTextLabel("I'm using mah RC vehicle to pwn ya nubs!", 0x008080FF, Pos[0], Pos[1], Pos[2] + 5, 0.0, 0, 1);
}

forward OnPlayerExitStreakRcVehicle(playerid);
public OnPlayerExitStreakRcVehicle(playerid)
{
    Delete3DTextLabel(DrivingRCText[playerid]);
}