Changing pins 2,3,7

Hi, i'm in the middle of a gsm thermostat project and i'm stuck with some pins overlapping...
this is my current setup:

  • Arduino Uno R3
  • Arduino GSM Shield v2
  • Pixnor Uno R3 TFT 2.8'' Shield

The problem is that if i connect the TFT on top of the GSM shield, the TFT shows a blank (white) screen.
Both the shields individually attached to the Arduino board work:
Arduino+TFT = OK
Arduino-GSM = OK
Arduino +GSM + TFT = KO

pls, see pic attached: backlight is working, touchscreen is working i can see it via serial, but screens remains white

I learned (too late!) that both the GSM and the TFT shield use pins 2,3,7
so i need to change the GSM pin layout (i could change the TFT pins but it seems more difficult at a first glance)

i noticed, in GSM3SoftSerial.cpp (GSM library)
at about line #41

#if defined(__AVR_ATmega328P__) 
#define __TXPIN__ 3
#define __RXPIN__ 2
#define __RXINT__ 3
#elif defined(__AVR_ATmega2560__) || defined(__AVR_ATmega1280__)
#elif defined(__AVR_ATmega32U4__)

and then in GSM3ShieldV1.cpp

#define __RESETPIN__ 7

Do you guys think i safely try changing these values to my preferred pins (ideally 11-12-13)
and of course put some jumpers accordingly between the 2,3,7 pins on the shield and the new ones defined via software?

oh and of course any other ideas are really appreciated

ok you can close this. i made it.
surely not thanks to the help received here...

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