Wow.  One I can Answer :-)

GP3 is defined as input only.  Sorry.

GP2  is also MCLRE so you will have to "config" it to be OFF.

Here is my config line  (12C508) using MPASM via MPLAB

__config _CP_OFF & _WDT_ON  & _IntRC_OSC & _MCLRE_OFF

Be aware that the Wakeup on bit change doesn't work on all pins
either.

Chuck