If I go from a stock Rad in 67 289 to 4 core Rad will I have to worry about the space between my fan and Rad.I have a clutch fan set up with a shroud will it still work.

 

It will fit, but you'll have to slide the fan and shroud in together. Or, bolt the shroud to the radiator, then lower the radiator, shroud and fan in all at the same time. When installed, my A/C compressor is VERY close to the shroud, but doesn't touch.