I have the same thing happen to me, but it only hairline fractured so it only lost preassure at High RPM, luckily i was only driving around Oran Park practising at the time, but when i went to undo it it snapped completely
T pieces are bad for 4AGE's,
Easy outs should do the trick, just dont exert too much downward preassure on the block while trying to extract it, or you will have some welding to do as well.