Be careful choosing an aluminum radiator. There is a lot of science behind them, and a lot of lies. Not all radiators work the same. The 1" tube is a good idea, especially if you can use a 2 row. Some companies put them inline, some stagger them for compactness. My thought is that much larger than 1" and, although you are flowing a lot of coolant, not enough is getting any surface cooling for the engine. I think a sacrificial radiator cap is a good idea also. It has an anode sticking out of it that erodes away from acids and/or alkalies that build up in the cooling system.