please help....anyone...have a 340. I rebuilt it in 05.from then it has over heated terribly,every time I try to run it . consensquently I parked it and all but forgot it.from an accident prior to me owning the car,a six cylinder radiator was installed,when I rebuilt the motor I changed it back to a v8 radiator.upon rebuilding of course ,a new water pump was installed along with hoses and belt.that is all that's changed.since rebuild,the lower rad hose collapses.last month I tore it down,replaced head gaskets and added a heavy duty(believe it)lower rad hose. it no longer collapses but still over heats. radiator seems to be primo condtion,very clean far as I can tell.thermostat is out. timing is 2-3 btdc.stumped totally.any ideas??? anyone.......help.