Hi everyone. I'm a long term LS6 '04 V1 owner (and lover), but I now have a problem that has me stumped.

Had a radiator replacement (small accident) done at a shop, and now cannot get the damn thing bled (no heat, hear the classic gurgling in the dash). I completely removed the LS6 bleeder from the front of the passenger side head, loosened the other, overfilled the coolant cold, and get nothing out of the bleeders. Jacked up the front, ran up to temp until the thermostat opened, still nothing.

One other weird thing, the overflow tank is not hot at all (though the level did rise when warm).

Any good LS6 mechanics here?