First, pick the pin you want to remap to.
Second, pick the input function you want to remap.
Third, identify the required configuration register/field.
In this example, the main function display a single toggling LED on RB15 - a heartbeat. Since INT0 is already on RB7, INT1 is mapped to RB6 and INT2 is mapped to RB5. INT0 is set at priority 1 while INT1 is at Priority 2 and INT2 is at priority 3. This means INT0 can only interrupt the heartbeat while INT1 can interrupt both INT0 and the heartbeat and INT2 can interrupt everything.