We have a 20 inch 1967 aluminum radiator in The 66.
We upgraded from the 17 inch to the 20 inch wide one for better cooling. We had to cut 1 1/2 inches from each side of the radiator support to allow air to flow to all of the radiator
Pictures and Info: Cooling
Mustang Steve has a write up on putting in a 24 inch radiator in a 66. radiators
There are many dealers and Ebay dealers that sell them. Prices will range from 130 to 350.
You don't need to "hack" your rad support system to improve your cooling. I run a 4 row copper with a 180 deg. T/S with an engine that makes 392 RWHP. I have no cooling problems on a 95 degree day.
Check with Redline cooling, if you want to go aluminum.
The Champion I got fit perfectly, is guaranteed to your satisfaction, is less expensive than a comparable brass radiator and can be purchased with or without an electric fan. The quality is of the highest I have seen on any radiator and much better than the ford three row.
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