[Scarebird]

One of the other issues I was having was burping the cooling system. I belatedly realised that the upper hose was creating an air pocket as it was almost 4" higher than the radiators inlet port.



Some research initially revealed nothing for hoses, then I got lucky. I was going thru LS powered vehicles and noted this Dayco 70815 hose from a 2010 Camaro. It used an offset hose in 1-1/4" ID, so it would clear the power steering pump and fan also. They are $11 on Amazon.



I was able to trim it and the 1969 GTO upper hose to sit at the same level as the inlet. I will fire it up tomorrow when it stops raining and see how it burps the air.