Champion radiator for ~500hp small block??

I experienced the same thing when I picked up a 3 core Champion radiator for my Dart. Very little room between the water pump pulley and the electric fans. I'd like to run a mechanical fan/clutch if possible.
I also bet you had a good little bit of room between the core and the radiator support. That's how mine is. I'm tempted to take to a friend who can TIG and let him relocate the side brackets so the core will be moved toward the front of the car, giving me a little more space.