Having troubles getting the RSSI Value of an XBee

Hello, ive been working on this project for quite a while now this is the setup:

I have 4 Arduino boards sending packets to a central arduino, what i want to do is get the RSSI values of each data packet im receiveng (meaning, the average rssi value from node #1 to #4), right now i can only read the frame information on the receiver (Im working in API mode), but i cant figure out a way to reach the RSSI value and then store it into a variable.

Here are both my codes:

TX

byte Router_on[] = {0x7E, 0x00, 0x0C, 0x00, 0x01, 0x00, 0x13, 0xA2, 0x00, 0x40, 0xD8, 0x36, 0xC5, 0x00, 0x41, 0xF5};
int c = 0;

void setup()
{
Serial.begin(9600);
delay(62+random(100));
for ( int c=0; c<100; c++) {
Serial.write(Router_on, 16);
delay (100+random(100));
}

}
void loop() {

}

RX:

int c = 0;
int temp = 0;

void setup()
{
Serial.begin(9600);
delay(500);

}

void loop() {
while (c < 1) {
if (Serial.available() > 10){
Serial.println("Comunicacion Exitosa");
c++;
}
}

if (Serial.available() > 10) {
for (int i=0; i<10; i++){
Serial.print(Serial.read(),HEX);
Serial.print(",");
}
Serial.println();
}
}

Just out of curiosity, what are you thinking you'd use the RSSI value for?