240sx Overheating

95 240sx is overheating. It started with a leaking heater core. Put (2) cans of liquid aluminum for radiators. Didn't work so disconnected heater core and added bypass hose. Still ran hot so I pulled the thermostat. Still running hot. I'm guessing the radiator is plugged and Not circulating. Any suggestions.........95 240 Radiators are hard to come by and expensive.......Already replaced once because part of the plastic blew out..........

get a koyo aluminium radiator