90 chev 1/2 ton...no heat up in Canada....OOOOOOOOOOOOOHHHHHHHHHH

[roonie]

I just bought a 1990 chevy 1/2 ton 2wd (c)(305cid)with air cond.It seems to have been a bit neglected but the price was right i guess.Ha Ha!!I have barely any heat comming from heater.One heater core hose is hot,the other cold.this truck has a nipple type restrictor screwed into the intake going to the heater core.it is half metal pipe then the rest is rubber hose.I just replaced the nipple as it was swollen shut and pluqqed. should i remove it and put a screw in hose stub and have no restrictor like others are doing.
also the engine temp is hovering around 65 (celcius)a far cry from what it should be.I have installed a second thermostat as when i boiled water the cheaper 1st thermostat barely opened at 210 F.Even the new more expensive Superstat only opens 1/4 inch at 210F.what gives?When i remove the rad cap the fluid from the heater core comes into the rad at only a trickle,then when i rev the engine it increases but only slightly.Also the fluid in the rad repeatedly comes up and spills over then goes back down again.this happens every 20 seconds or so.do i have an air lock?when i feel the top rad hose it is only hot near the thermostat housing and again at the rad.not much in between those spots for heat.I have also installed a new water pump as the other one leaked.this heat problem also occured before the new water pump.If the system was full of sediment would i not be overheating instead of running too cold?any help for this problem would be greatly appreciated as winter is fast approaching up here in Canada.thanks.I would also at this time like to state how awesome of a site this is!!!It will hopefully keep the shop owners more honest etc.the whole industry needs a revamp!!!!