Thermostat housing nipple removal

[Rev Run D]

Trying to delete my throttle body coolant lines using Garagistic's method http://garagistic.com/index.php?page...-heater-delete, and I'm stuck.

I can't seem to punch out the sleeve. Cut the nipple off so no way going back. My punch gets stuck due to the angle; any tips?

[digger]

drill and tap it then pull out out with a bolt or just drill it out