Looking to put a new radiator in my 89

I am looking at the CSF radiator for $155. I want to go with a open system and was told the radiator with a filler cap will bolt right up but I would have to do a few things to make it work. What would i have to do? And is it better to just stay closed and buy the filler cap from auto zone?

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I thought about switching to the open system a lot but after reading this thread I decided when I replaced my radiator I'd keep it a closed system and just buy some kind of metal expansion tank with a real rad cap and hook up a plastic overflow tank to the metal expansion tank as suggested in the thread. That would in essence convert it to an open system but you also can have the rad cap at the highest point and not worry about the temp sensor for the aux fan.