Bleeding cooling system

[C15_Sierra]

I'm running a stock '80 cooling system in my 5.3 swap, and I'm thinking over my lack of coolant flow issue. I thought it might be a new water pump, but now I'm doubting that and thinking that it's air-locked somehow.

I used '00 Silverado radiator hoses (my 5.3 is from a '00 Silverado), and the upper radiator hose runs up and across to the radiator inlet on the drivers side. I moved it down since it was the highest point in the system, but I'm still not getting any flow. It does seem like there's any coolant in there, so how can I bleed that hose so I can figure out if its indeed my water pump.

Previously, I replaced the thermostat, so I know that's good. Any other tips?