Coolant hose routing question

[68isgreat]

Hi guys, I have a 68 shorty stepside I've done a frame off on, and I'm installing a 1990 350 tbi motor in it with about 90k miles supposedly, and a newly rebuilt (supposedly) 700r4 with less than 1k miles on it. This was a farm truck with a six banger, so I'm starting from scratch. I just got a new painless harness and will be installing a rear efi tank soon. Right now, I have the coolant hose outlet at the rear of the intake manifold capped off, as well as the one from the top of my radiator, which is from a square body, so it has the two upper inlet hoses. Before I hook the hoses up to the heater core (the cab is still off the frame), I just want to see if it runs ok. Can I hook up the rear manifold outlet hose to the upper right outlet hose on the radiator temporarily just to see how it runs? I don't want it to overheat. Just want to make sure that's the correct coolant flow, from the rear outlet (which would normally go to the heater core inlet) and back to the radiator, which would flow down to the lower radiator hose and up to the water pump. I can post a pic if necessary.

Thanks!