radiator configuration

[orangeblossomspecial]

Radiator help please. I just pulled a blown engine out of my 86 pickup. I replaced it with a 350 out of a 71 gmc. everything worked fine (I removed all the crap) till I started it up. It over heats. I have one of the heater hoses running to the intake manifold, one to the radiator (that was the configuration on the 86) Now, no matter how hot it gets, the thermostat wont open. I have good circulation in the radiator but I wonder if the configuration is not letting pressure build behind the thermostat? Upper radiator hose never gets hot. Ive tried two new thermostats.

Thanks for the help

Those two on the deck.....thier no help. and the last pic is the engine Ive replaced. The boys said..."Dad, the engine light came on?"