Not sure why you are going through all the hassle?
You sholud be able to go from the 19" to 22" radiator without changing anything.A 22" radiator is more than enough for any aplication.
I was looking at the 64 rad support and realized id have to modify it alot in order for it open up enough to fit my 97 jeep grand cherokee radiator i bought. Using the 66 support, i only have to trim it open a little. The 64 rad support would look very butchered if i cut it open that much, the 66 support will only looked a touch widened to the trained eye.