infamous nissan coolant issues HELP!

[nd240sx3]

Alright people.. Ka24de got hotter then usual but not on H.. Replaced thermostat w/3 aftermarket now nissan, then lower hose would not get hot.. T stat not opening, bleeder screw on intake broken off by previous owner... Then i broke a easy out in said screw.. Use vacuum bleeder to add coolant which held vacuum. replaced water pump, radiator, and cap then hydro carbon tested coolant came up positive for exhaust fumes in coolant... Replaced headgasket with completely new decked head.. After head and gasket install with arp head studs i vacumm bled the coolant then used coolant funnel and jacked front end up. Vacuum bleeder held vacuum for 10 mins prior to releasing the valve. Still getting same symptoms, upper hose gets super hot and gurgles while lower hose stays ice cold.. Thought cracked block.. Yet no coolant in oil or vise versa, and holds vacuum, and holds pressure with coolant pressure tester when hot .. Is it just the infamous nissan air pocket or is my shit fubar!