Yes, you are referring to what is commonly called the "Shelby Control Arm Drop". For 1965-1966 cars, it consists of relocating the control arm studs 1 inch lower and 1/8 inch toward the rear of the car. I got my template from the inside of a Tony Branda catalog ( www.cobranda.com
), but it has been published many other places as well.
There's no reason why it cannot be done using your old control arms, but it can put more stress on your upper ball joints and you may want to replace them if you are dropping the arms.
I also suggest you take the paper template and reproduce it in thick sheetmetal, as that will make it much easier to accurately locate the holes.