'64 & '65 V8 radiators all have the upper inlet on the passenger side.
'66 & '67 radiators have it on the driver's side.
The later design radiator is a direct bolt-in on earlier cars, other than having to notch the fan shroud for the new inlet location.
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Sorry I have nothing to offer on modding the standard radiator support to fit the taller radiator.
But I can tell you that the A/C support sits pretty much even with the bottom of the bumper so there really isn't any room to spare. Scraping the bottom of the bumper isn't all that hard to do once or twice and if you do that once with a modded support that hangs below the bumper you'll be in for a big disappointment.
